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3,512
Minimum Operations to Make Array Sum Divisible by K
Easy
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>. You can perform the following operation any number of times:</p> <ul> <li>Select an index <code>i</code> and replace <code>nums[i]</code> with <code>nums[i] - 1</code>.</li> </ul> <p>Return the <strong>minimum</strong> number of operations required to make the sum of the array divisible by <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,9,7], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Perform 4 operations on <code>nums[1] = 9</code>. Now, <code>nums = [3, 5, 7]</code>.</li> <li>The sum is 15, which is divisible by 5.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,1,3], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The sum is 8, which is already divisible by 4. Hence, no operations are needed.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2], k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Perform 3 operations on <code>nums[0] = 3</code> and 2 operations on <code>nums[1] = 2</code>. Now, <code>nums = [0, 0]</code>.</li> <li>The sum is 0, which is divisible by 6.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 100</code></li> </ul>
Array; Math
Python
class Solution: def minOperations(self, nums: List[int], k: int) -> int: return sum(nums) % k
3,512
Minimum Operations to Make Array Sum Divisible by K
Easy
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>. You can perform the following operation any number of times:</p> <ul> <li>Select an index <code>i</code> and replace <code>nums[i]</code> with <code>nums[i] - 1</code>.</li> </ul> <p>Return the <strong>minimum</strong> number of operations required to make the sum of the array divisible by <code>k</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,9,7], k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Perform 4 operations on <code>nums[1] = 9</code>. Now, <code>nums = [3, 5, 7]</code>.</li> <li>The sum is 15, which is divisible by 5.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,1,3], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The sum is 8, which is already divisible by 4. Hence, no operations are needed.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2], k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Perform 3 operations on <code>nums[0] = 3</code> and 2 operations on <code>nums[1] = 2</code>. Now, <code>nums = [0, 0]</code>.</li> <li>The sum is 0, which is divisible by 6.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= 100</code></li> </ul>
Array; Math
TypeScript
function minOperations(nums: number[], k: number): number { return nums.reduce((acc, x) => acc + x, 0) % k; }
3,516
Find Closest Person
Easy
<p data-end="116" data-start="0">You are given three integers <code data-end="33" data-start="30">x</code>, <code data-end="38" data-start="35">y</code>, and <code data-end="47" data-start="44">z</code>, representing the positions of three people on a number line:</p> <ul data-end="252" data-start="118"> <li data-end="154" data-start="118"><code data-end="123" data-start="120">x</code> is the position of Person 1.</li> <li data-end="191" data-start="155"><code data-end="160" data-start="157">y</code> is the position of Person 2.</li> <li data-end="252" data-start="192"><code data-end="197" data-start="194">z</code> is the position of Person 3, who does <strong>not</strong> move.</li> </ul> <p data-end="322" data-start="254">Both Person 1 and Person 2 move toward Person 3 at the <strong>same</strong> speed.</p> <p data-end="372" data-start="324">Determine which person reaches Person 3 <strong>first</strong>:</p> <ul data-end="505" data-start="374"> <li data-end="415" data-start="374">Return 1 if Person 1 arrives first.</li> <li data-end="457" data-start="416">Return 2 if Person 2 arrives first.</li> <li data-end="505" data-start="458">Return 0 if both arrive at the <strong>same</strong> time.</li> </ul> <p data-end="537" data-is-last-node="" data-is-only-node="" data-start="507">Return the result accordingly.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 7, z = 4</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul data-end="258" data-start="113"> <li data-end="193" data-start="113">Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.</li> <li data-end="258" data-start="194">Person 2 is at position 7 and can reach Person 3 in 3 steps.</li> </ul> <p data-end="317" data-is-last-node="" data-is-only-node="" data-start="260">Since Person 1 reaches Person 3 first, the output is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 5, z = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 2 and can reach Person 3 (at position 6) in 4 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 1 step.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since Person 2 reaches Person 3 first, the output is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 1, y = 5, z = 3</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 1 and can reach Person 3 (at position 3) in 2 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 2 steps.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since both Person 1 and Person 2 reach Person 3 at the same time, the output is 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= x, y, z &lt;= 100</code></li> </ul>
Math
C++
class Solution { public: int findClosest(int x, int y, int z) { int a = abs(x - z); int b = abs(y - z); return a == b ? 0 : (a < b ? 1 : 2); } };
3,516
Find Closest Person
Easy
<p data-end="116" data-start="0">You are given three integers <code data-end="33" data-start="30">x</code>, <code data-end="38" data-start="35">y</code>, and <code data-end="47" data-start="44">z</code>, representing the positions of three people on a number line:</p> <ul data-end="252" data-start="118"> <li data-end="154" data-start="118"><code data-end="123" data-start="120">x</code> is the position of Person 1.</li> <li data-end="191" data-start="155"><code data-end="160" data-start="157">y</code> is the position of Person 2.</li> <li data-end="252" data-start="192"><code data-end="197" data-start="194">z</code> is the position of Person 3, who does <strong>not</strong> move.</li> </ul> <p data-end="322" data-start="254">Both Person 1 and Person 2 move toward Person 3 at the <strong>same</strong> speed.</p> <p data-end="372" data-start="324">Determine which person reaches Person 3 <strong>first</strong>:</p> <ul data-end="505" data-start="374"> <li data-end="415" data-start="374">Return 1 if Person 1 arrives first.</li> <li data-end="457" data-start="416">Return 2 if Person 2 arrives first.</li> <li data-end="505" data-start="458">Return 0 if both arrive at the <strong>same</strong> time.</li> </ul> <p data-end="537" data-is-last-node="" data-is-only-node="" data-start="507">Return the result accordingly.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 7, z = 4</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul data-end="258" data-start="113"> <li data-end="193" data-start="113">Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.</li> <li data-end="258" data-start="194">Person 2 is at position 7 and can reach Person 3 in 3 steps.</li> </ul> <p data-end="317" data-is-last-node="" data-is-only-node="" data-start="260">Since Person 1 reaches Person 3 first, the output is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 5, z = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 2 and can reach Person 3 (at position 6) in 4 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 1 step.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since Person 2 reaches Person 3 first, the output is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 1, y = 5, z = 3</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 1 and can reach Person 3 (at position 3) in 2 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 2 steps.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since both Person 1 and Person 2 reach Person 3 at the same time, the output is 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= x, y, z &lt;= 100</code></li> </ul>
Math
Go
func findClosest(x int, y int, z int) int { a, b := abs(x-z), abs(y-z) if a == b { return 0 } if a < b { return 1 } return 2 } func abs(x int) int { if x < 0 { return -x } return x }
3,516
Find Closest Person
Easy
<p data-end="116" data-start="0">You are given three integers <code data-end="33" data-start="30">x</code>, <code data-end="38" data-start="35">y</code>, and <code data-end="47" data-start="44">z</code>, representing the positions of three people on a number line:</p> <ul data-end="252" data-start="118"> <li data-end="154" data-start="118"><code data-end="123" data-start="120">x</code> is the position of Person 1.</li> <li data-end="191" data-start="155"><code data-end="160" data-start="157">y</code> is the position of Person 2.</li> <li data-end="252" data-start="192"><code data-end="197" data-start="194">z</code> is the position of Person 3, who does <strong>not</strong> move.</li> </ul> <p data-end="322" data-start="254">Both Person 1 and Person 2 move toward Person 3 at the <strong>same</strong> speed.</p> <p data-end="372" data-start="324">Determine which person reaches Person 3 <strong>first</strong>:</p> <ul data-end="505" data-start="374"> <li data-end="415" data-start="374">Return 1 if Person 1 arrives first.</li> <li data-end="457" data-start="416">Return 2 if Person 2 arrives first.</li> <li data-end="505" data-start="458">Return 0 if both arrive at the <strong>same</strong> time.</li> </ul> <p data-end="537" data-is-last-node="" data-is-only-node="" data-start="507">Return the result accordingly.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 7, z = 4</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul data-end="258" data-start="113"> <li data-end="193" data-start="113">Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.</li> <li data-end="258" data-start="194">Person 2 is at position 7 and can reach Person 3 in 3 steps.</li> </ul> <p data-end="317" data-is-last-node="" data-is-only-node="" data-start="260">Since Person 1 reaches Person 3 first, the output is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 5, z = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 2 and can reach Person 3 (at position 6) in 4 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 1 step.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since Person 2 reaches Person 3 first, the output is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 1, y = 5, z = 3</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 1 and can reach Person 3 (at position 3) in 2 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 2 steps.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since both Person 1 and Person 2 reach Person 3 at the same time, the output is 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= x, y, z &lt;= 100</code></li> </ul>
Math
Java
class Solution { public int findClosest(int x, int y, int z) { int a = Math.abs(x - z); int b = Math.abs(y - z); return a == b ? 0 : (a < b ? 1 : 2); } }
3,516
Find Closest Person
Easy
<p data-end="116" data-start="0">You are given three integers <code data-end="33" data-start="30">x</code>, <code data-end="38" data-start="35">y</code>, and <code data-end="47" data-start="44">z</code>, representing the positions of three people on a number line:</p> <ul data-end="252" data-start="118"> <li data-end="154" data-start="118"><code data-end="123" data-start="120">x</code> is the position of Person 1.</li> <li data-end="191" data-start="155"><code data-end="160" data-start="157">y</code> is the position of Person 2.</li> <li data-end="252" data-start="192"><code data-end="197" data-start="194">z</code> is the position of Person 3, who does <strong>not</strong> move.</li> </ul> <p data-end="322" data-start="254">Both Person 1 and Person 2 move toward Person 3 at the <strong>same</strong> speed.</p> <p data-end="372" data-start="324">Determine which person reaches Person 3 <strong>first</strong>:</p> <ul data-end="505" data-start="374"> <li data-end="415" data-start="374">Return 1 if Person 1 arrives first.</li> <li data-end="457" data-start="416">Return 2 if Person 2 arrives first.</li> <li data-end="505" data-start="458">Return 0 if both arrive at the <strong>same</strong> time.</li> </ul> <p data-end="537" data-is-last-node="" data-is-only-node="" data-start="507">Return the result accordingly.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 7, z = 4</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul data-end="258" data-start="113"> <li data-end="193" data-start="113">Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.</li> <li data-end="258" data-start="194">Person 2 is at position 7 and can reach Person 3 in 3 steps.</li> </ul> <p data-end="317" data-is-last-node="" data-is-only-node="" data-start="260">Since Person 1 reaches Person 3 first, the output is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 5, z = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 2 and can reach Person 3 (at position 6) in 4 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 1 step.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since Person 2 reaches Person 3 first, the output is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 1, y = 5, z = 3</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 1 and can reach Person 3 (at position 3) in 2 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 2 steps.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since both Person 1 and Person 2 reach Person 3 at the same time, the output is 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= x, y, z &lt;= 100</code></li> </ul>
Math
Python
class Solution: def findClosest(self, x: int, y: int, z: int) -> int: a = abs(x - z) b = abs(y - z) return 0 if a == b else (1 if a < b else 2)
3,516
Find Closest Person
Easy
<p data-end="116" data-start="0">You are given three integers <code data-end="33" data-start="30">x</code>, <code data-end="38" data-start="35">y</code>, and <code data-end="47" data-start="44">z</code>, representing the positions of three people on a number line:</p> <ul data-end="252" data-start="118"> <li data-end="154" data-start="118"><code data-end="123" data-start="120">x</code> is the position of Person 1.</li> <li data-end="191" data-start="155"><code data-end="160" data-start="157">y</code> is the position of Person 2.</li> <li data-end="252" data-start="192"><code data-end="197" data-start="194">z</code> is the position of Person 3, who does <strong>not</strong> move.</li> </ul> <p data-end="322" data-start="254">Both Person 1 and Person 2 move toward Person 3 at the <strong>same</strong> speed.</p> <p data-end="372" data-start="324">Determine which person reaches Person 3 <strong>first</strong>:</p> <ul data-end="505" data-start="374"> <li data-end="415" data-start="374">Return 1 if Person 1 arrives first.</li> <li data-end="457" data-start="416">Return 2 if Person 2 arrives first.</li> <li data-end="505" data-start="458">Return 0 if both arrive at the <strong>same</strong> time.</li> </ul> <p data-end="537" data-is-last-node="" data-is-only-node="" data-start="507">Return the result accordingly.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 7, z = 4</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul data-end="258" data-start="113"> <li data-end="193" data-start="113">Person 1 is at position 2 and can reach Person 3 (at position 4) in 2 steps.</li> <li data-end="258" data-start="194">Person 2 is at position 7 and can reach Person 3 in 3 steps.</li> </ul> <p data-end="317" data-is-last-node="" data-is-only-node="" data-start="260">Since Person 1 reaches Person 3 first, the output is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 2, y = 5, z = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 2 and can reach Person 3 (at position 6) in 4 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 1 step.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since Person 2 reaches Person 3 first, the output is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">x = 1, y = 5, z = 3</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul data-end="245" data-start="92"> <li data-end="174" data-start="92">Person 1 is at position 1 and can reach Person 3 (at position 3) in 2 steps.</li> <li data-end="245" data-start="175">Person 2 is at position 5 and can reach Person 3 in 2 steps.</li> </ul> <p data-end="304" data-is-last-node="" data-is-only-node="" data-start="247">Since both Person 1 and Person 2 reach Person 3 at the same time, the output is 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= x, y, z &lt;= 100</code></li> </ul>
Math
TypeScript
function findClosest(x: number, y: number, z: number): number { const a = Math.abs(x - z); const b = Math.abs(y - z); return a === b ? 0 : a < b ? 1 : 2; }
3,522
Calculate Score After Performing Instructions
Medium
<p>You are given two arrays, <code>instructions</code> and <code>values</code>, both of size <code>n</code>.</p> <p>You need to simulate a process based on the following rules:</p> <ul> <li>You start at the first instruction at index <code>i = 0</code> with an initial score of 0.</li> <li>If <code>instructions[i]</code> is <code>&quot;add&quot;</code>: <ul> <li>Add <code>values[i]</code> to your score.</li> <li>Move to the next instruction <code>(i + 1)</code>.</li> </ul> </li> <li>If <code>instructions[i]</code> is <code>&quot;jump&quot;</code>: <ul> <li>Move to the instruction at index <code>(i + values[i])</code> without modifying your score.</li> </ul> </li> </ul> <p>The process ends when you either:</p> <ul> <li>Go out of bounds (i.e., <code>i &lt; 0 or i &gt;= n</code>), or</li> <li>Attempt to revisit an instruction that has been previously executed. The revisited instruction is not executed.</li> </ul> <p>Return your score at the end of the process.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;,&quot;jump&quot;,&quot;add&quot;,&quot;jump&quot;], values = [2,1,3,1,-2,-3]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 2 = 2</code>.</li> <li>At index 2: Instruction is <code>&quot;add&quot;</code>, add <code>values[2] = 3</code> to your score and move to index 3. Your score becomes 3.</li> <li>At index 3: Instruction is <code>&quot;jump&quot;</code>, move to index <code>3 + 1 = 4</code>.</li> <li>At index 4: Instruction is <code>&quot;add&quot;</code>, add <code>values[4] = -2</code> to your score and move to index 5. Your score becomes 1.</li> <li>At index 5: Instruction is <code>&quot;jump&quot;</code>, move to index <code>5 + (-3) = 2</code>.</li> <li>At index 2: Already visited. The process ends.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;], values = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 3 = 3</code>.</li> <li>At index 3: Out of bounds. The process ends.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;], values = [0]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 0 = 0</code>.</li> <li>At index 0: Already visited. The process ends.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == instructions.length == values.length</code></li> <li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>instructions[i]</code> is either <code>&quot;add&quot;</code> or <code>&quot;jump&quot;</code>.</li> <li><code>-10<sup>5</sup> &lt;= values[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; String; Simulation
C++
class Solution { public: long long calculateScore(vector<string>& instructions, vector<int>& values) { int n = values.size(); vector<bool> vis(n, false); long long ans = 0; int i = 0; while (i >= 0 && i < n && !vis[i]) { vis[i] = true; if (instructions[i][0] == 'a') { ans += values[i]; i += 1; } else { i += values[i]; } } return ans; } };
3,522
Calculate Score After Performing Instructions
Medium
<p>You are given two arrays, <code>instructions</code> and <code>values</code>, both of size <code>n</code>.</p> <p>You need to simulate a process based on the following rules:</p> <ul> <li>You start at the first instruction at index <code>i = 0</code> with an initial score of 0.</li> <li>If <code>instructions[i]</code> is <code>&quot;add&quot;</code>: <ul> <li>Add <code>values[i]</code> to your score.</li> <li>Move to the next instruction <code>(i + 1)</code>.</li> </ul> </li> <li>If <code>instructions[i]</code> is <code>&quot;jump&quot;</code>: <ul> <li>Move to the instruction at index <code>(i + values[i])</code> without modifying your score.</li> </ul> </li> </ul> <p>The process ends when you either:</p> <ul> <li>Go out of bounds (i.e., <code>i &lt; 0 or i &gt;= n</code>), or</li> <li>Attempt to revisit an instruction that has been previously executed. The revisited instruction is not executed.</li> </ul> <p>Return your score at the end of the process.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;,&quot;jump&quot;,&quot;add&quot;,&quot;jump&quot;], values = [2,1,3,1,-2,-3]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 2 = 2</code>.</li> <li>At index 2: Instruction is <code>&quot;add&quot;</code>, add <code>values[2] = 3</code> to your score and move to index 3. Your score becomes 3.</li> <li>At index 3: Instruction is <code>&quot;jump&quot;</code>, move to index <code>3 + 1 = 4</code>.</li> <li>At index 4: Instruction is <code>&quot;add&quot;</code>, add <code>values[4] = -2</code> to your score and move to index 5. Your score becomes 1.</li> <li>At index 5: Instruction is <code>&quot;jump&quot;</code>, move to index <code>5 + (-3) = 2</code>.</li> <li>At index 2: Already visited. The process ends.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;], values = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 3 = 3</code>.</li> <li>At index 3: Out of bounds. The process ends.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;], values = [0]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 0 = 0</code>.</li> <li>At index 0: Already visited. The process ends.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == instructions.length == values.length</code></li> <li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>instructions[i]</code> is either <code>&quot;add&quot;</code> or <code>&quot;jump&quot;</code>.</li> <li><code>-10<sup>5</sup> &lt;= values[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; String; Simulation
Go
func calculateScore(instructions []string, values []int) (ans int64) { n := len(values) vis := make([]bool, n) i := 0 for i >= 0 && i < n && !vis[i] { vis[i] = true if instructions[i][0] == 'a' { ans += int64(values[i]) i += 1 } else { i += values[i] } } return }
3,522
Calculate Score After Performing Instructions
Medium
<p>You are given two arrays, <code>instructions</code> and <code>values</code>, both of size <code>n</code>.</p> <p>You need to simulate a process based on the following rules:</p> <ul> <li>You start at the first instruction at index <code>i = 0</code> with an initial score of 0.</li> <li>If <code>instructions[i]</code> is <code>&quot;add&quot;</code>: <ul> <li>Add <code>values[i]</code> to your score.</li> <li>Move to the next instruction <code>(i + 1)</code>.</li> </ul> </li> <li>If <code>instructions[i]</code> is <code>&quot;jump&quot;</code>: <ul> <li>Move to the instruction at index <code>(i + values[i])</code> without modifying your score.</li> </ul> </li> </ul> <p>The process ends when you either:</p> <ul> <li>Go out of bounds (i.e., <code>i &lt; 0 or i &gt;= n</code>), or</li> <li>Attempt to revisit an instruction that has been previously executed. The revisited instruction is not executed.</li> </ul> <p>Return your score at the end of the process.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;,&quot;jump&quot;,&quot;add&quot;,&quot;jump&quot;], values = [2,1,3,1,-2,-3]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 2 = 2</code>.</li> <li>At index 2: Instruction is <code>&quot;add&quot;</code>, add <code>values[2] = 3</code> to your score and move to index 3. Your score becomes 3.</li> <li>At index 3: Instruction is <code>&quot;jump&quot;</code>, move to index <code>3 + 1 = 4</code>.</li> <li>At index 4: Instruction is <code>&quot;add&quot;</code>, add <code>values[4] = -2</code> to your score and move to index 5. Your score becomes 1.</li> <li>At index 5: Instruction is <code>&quot;jump&quot;</code>, move to index <code>5 + (-3) = 2</code>.</li> <li>At index 2: Already visited. The process ends.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;], values = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 3 = 3</code>.</li> <li>At index 3: Out of bounds. The process ends.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;], values = [0]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 0 = 0</code>.</li> <li>At index 0: Already visited. The process ends.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == instructions.length == values.length</code></li> <li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>instructions[i]</code> is either <code>&quot;add&quot;</code> or <code>&quot;jump&quot;</code>.</li> <li><code>-10<sup>5</sup> &lt;= values[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; String; Simulation
Java
class Solution { public long calculateScore(String[] instructions, int[] values) { int n = values.length; boolean[] vis = new boolean[n]; long ans = 0; int i = 0; while (i >= 0 && i < n && !vis[i]) { vis[i] = true; if (instructions[i].charAt(0) == 'a') { ans += values[i]; i += 1; } else { i = i + values[i]; } } return ans; } }
3,522
Calculate Score After Performing Instructions
Medium
<p>You are given two arrays, <code>instructions</code> and <code>values</code>, both of size <code>n</code>.</p> <p>You need to simulate a process based on the following rules:</p> <ul> <li>You start at the first instruction at index <code>i = 0</code> with an initial score of 0.</li> <li>If <code>instructions[i]</code> is <code>&quot;add&quot;</code>: <ul> <li>Add <code>values[i]</code> to your score.</li> <li>Move to the next instruction <code>(i + 1)</code>.</li> </ul> </li> <li>If <code>instructions[i]</code> is <code>&quot;jump&quot;</code>: <ul> <li>Move to the instruction at index <code>(i + values[i])</code> without modifying your score.</li> </ul> </li> </ul> <p>The process ends when you either:</p> <ul> <li>Go out of bounds (i.e., <code>i &lt; 0 or i &gt;= n</code>), or</li> <li>Attempt to revisit an instruction that has been previously executed. The revisited instruction is not executed.</li> </ul> <p>Return your score at the end of the process.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;,&quot;jump&quot;,&quot;add&quot;,&quot;jump&quot;], values = [2,1,3,1,-2,-3]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 2 = 2</code>.</li> <li>At index 2: Instruction is <code>&quot;add&quot;</code>, add <code>values[2] = 3</code> to your score and move to index 3. Your score becomes 3.</li> <li>At index 3: Instruction is <code>&quot;jump&quot;</code>, move to index <code>3 + 1 = 4</code>.</li> <li>At index 4: Instruction is <code>&quot;add&quot;</code>, add <code>values[4] = -2</code> to your score and move to index 5. Your score becomes 1.</li> <li>At index 5: Instruction is <code>&quot;jump&quot;</code>, move to index <code>5 + (-3) = 2</code>.</li> <li>At index 2: Already visited. The process ends.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;], values = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 3 = 3</code>.</li> <li>At index 3: Out of bounds. The process ends.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;], values = [0]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 0 = 0</code>.</li> <li>At index 0: Already visited. The process ends.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == instructions.length == values.length</code></li> <li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>instructions[i]</code> is either <code>&quot;add&quot;</code> or <code>&quot;jump&quot;</code>.</li> <li><code>-10<sup>5</sup> &lt;= values[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; String; Simulation
Python
class Solution: def calculateScore(self, instructions: List[str], values: List[int]) -> int: n = len(values) vis = [False] * n ans = i = 0 while 0 <= i < n and not vis[i]: vis[i] = True if instructions[i][0] == "a": ans += values[i] i += 1 else: i = i + values[i] return ans
3,522
Calculate Score After Performing Instructions
Medium
<p>You are given two arrays, <code>instructions</code> and <code>values</code>, both of size <code>n</code>.</p> <p>You need to simulate a process based on the following rules:</p> <ul> <li>You start at the first instruction at index <code>i = 0</code> with an initial score of 0.</li> <li>If <code>instructions[i]</code> is <code>&quot;add&quot;</code>: <ul> <li>Add <code>values[i]</code> to your score.</li> <li>Move to the next instruction <code>(i + 1)</code>.</li> </ul> </li> <li>If <code>instructions[i]</code> is <code>&quot;jump&quot;</code>: <ul> <li>Move to the instruction at index <code>(i + values[i])</code> without modifying your score.</li> </ul> </li> </ul> <p>The process ends when you either:</p> <ul> <li>Go out of bounds (i.e., <code>i &lt; 0 or i &gt;= n</code>), or</li> <li>Attempt to revisit an instruction that has been previously executed. The revisited instruction is not executed.</li> </ul> <p>Return your score at the end of the process.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;,&quot;jump&quot;,&quot;add&quot;,&quot;jump&quot;], values = [2,1,3,1,-2,-3]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 2 = 2</code>.</li> <li>At index 2: Instruction is <code>&quot;add&quot;</code>, add <code>values[2] = 3</code> to your score and move to index 3. Your score becomes 3.</li> <li>At index 3: Instruction is <code>&quot;jump&quot;</code>, move to index <code>3 + 1 = 4</code>.</li> <li>At index 4: Instruction is <code>&quot;add&quot;</code>, add <code>values[4] = -2</code> to your score and move to index 5. Your score becomes 1.</li> <li>At index 5: Instruction is <code>&quot;jump&quot;</code>, move to index <code>5 + (-3) = 2</code>.</li> <li>At index 2: Already visited. The process ends.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;,&quot;add&quot;,&quot;add&quot;], values = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 3 = 3</code>.</li> <li>At index 3: Out of bounds. The process ends.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">instructions = [&quot;jump&quot;], values = [0]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>Simulate the process starting at instruction 0:</p> <ul> <li>At index 0: Instruction is <code>&quot;jump&quot;</code>, move to index <code>0 + 0 = 0</code>.</li> <li>At index 0: Already visited. The process ends.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == instructions.length == values.length</code></li> <li><code>1 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>instructions[i]</code> is either <code>&quot;add&quot;</code> or <code>&quot;jump&quot;</code>.</li> <li><code>-10<sup>5</sup> &lt;= values[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; String; Simulation
TypeScript
function calculateScore(instructions: string[], values: number[]): number { const n = values.length; const vis: boolean[] = Array(n).fill(false); let ans = 0; let i = 0; while (i >= 0 && i < n && !vis[i]) { vis[i] = true; if (instructions[i][0] === 'a') { ans += values[i]; i += 1; } else { i += values[i]; } } return ans; }
3,523
Make Array Non-decreasing
Medium
<p>You are given an integer array <code>nums</code>. In one operation, you can select a <span data-keyword="subarray-nonempty">subarray</span> and replace it with a single element equal to its <strong>maximum</strong> value.</p> <p>Return the <strong>maximum possible size</strong> of the array after performing zero or more operations such that the resulting array is <strong>non-decreasing</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,2,5,3,5]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>One way to achieve the maximum size is:</p> <ol> <li>Replace subarray <code>nums[1..2] = [2, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 3, 5]</code>.</li> <li>Replace subarray <code>nums[2..3] = [3, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 5]</code>.</li> </ol> <p>The final array <code>[4, 5, 5]</code> is non-decreasing with size <font face="monospace">3.</font></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>No operation is needed as the array <code>[1,2,3]</code> is already non-decreasing.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 2 * 10<sup>5</sup></code></li> </ul>
Stack; Greedy; Array; Monotonic Stack
C++
class Solution { public: int maximumPossibleSize(vector<int>& nums) { int ans = 0, mx = 0; for (int x : nums) { if (mx <= x) { ++ans; mx = x; } } return ans; } };
3,523
Make Array Non-decreasing
Medium
<p>You are given an integer array <code>nums</code>. In one operation, you can select a <span data-keyword="subarray-nonempty">subarray</span> and replace it with a single element equal to its <strong>maximum</strong> value.</p> <p>Return the <strong>maximum possible size</strong> of the array after performing zero or more operations such that the resulting array is <strong>non-decreasing</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,2,5,3,5]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>One way to achieve the maximum size is:</p> <ol> <li>Replace subarray <code>nums[1..2] = [2, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 3, 5]</code>.</li> <li>Replace subarray <code>nums[2..3] = [3, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 5]</code>.</li> </ol> <p>The final array <code>[4, 5, 5]</code> is non-decreasing with size <font face="monospace">3.</font></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>No operation is needed as the array <code>[1,2,3]</code> is already non-decreasing.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 2 * 10<sup>5</sup></code></li> </ul>
Stack; Greedy; Array; Monotonic Stack
Go
func maximumPossibleSize(nums []int) int { ans, mx := 0, 0 for _, x := range nums { if mx <= x { ans++ mx = x } } return ans }
3,523
Make Array Non-decreasing
Medium
<p>You are given an integer array <code>nums</code>. In one operation, you can select a <span data-keyword="subarray-nonempty">subarray</span> and replace it with a single element equal to its <strong>maximum</strong> value.</p> <p>Return the <strong>maximum possible size</strong> of the array after performing zero or more operations such that the resulting array is <strong>non-decreasing</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,2,5,3,5]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>One way to achieve the maximum size is:</p> <ol> <li>Replace subarray <code>nums[1..2] = [2, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 3, 5]</code>.</li> <li>Replace subarray <code>nums[2..3] = [3, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 5]</code>.</li> </ol> <p>The final array <code>[4, 5, 5]</code> is non-decreasing with size <font face="monospace">3.</font></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>No operation is needed as the array <code>[1,2,3]</code> is already non-decreasing.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 2 * 10<sup>5</sup></code></li> </ul>
Stack; Greedy; Array; Monotonic Stack
Java
class Solution { public int maximumPossibleSize(int[] nums) { int ans = 0, mx = 0; for (int x : nums) { if (mx <= x) { ++ans; mx = x; } } return ans; } }
3,523
Make Array Non-decreasing
Medium
<p>You are given an integer array <code>nums</code>. In one operation, you can select a <span data-keyword="subarray-nonempty">subarray</span> and replace it with a single element equal to its <strong>maximum</strong> value.</p> <p>Return the <strong>maximum possible size</strong> of the array after performing zero or more operations such that the resulting array is <strong>non-decreasing</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,2,5,3,5]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>One way to achieve the maximum size is:</p> <ol> <li>Replace subarray <code>nums[1..2] = [2, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 3, 5]</code>.</li> <li>Replace subarray <code>nums[2..3] = [3, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 5]</code>.</li> </ol> <p>The final array <code>[4, 5, 5]</code> is non-decreasing with size <font face="monospace">3.</font></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>No operation is needed as the array <code>[1,2,3]</code> is already non-decreasing.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 2 * 10<sup>5</sup></code></li> </ul>
Stack; Greedy; Array; Monotonic Stack
Python
class Solution: def maximumPossibleSize(self, nums: List[int]) -> int: ans = mx = 0 for x in nums: if mx <= x: ans += 1 mx = x return ans
3,523
Make Array Non-decreasing
Medium
<p>You are given an integer array <code>nums</code>. In one operation, you can select a <span data-keyword="subarray-nonempty">subarray</span> and replace it with a single element equal to its <strong>maximum</strong> value.</p> <p>Return the <strong>maximum possible size</strong> of the array after performing zero or more operations such that the resulting array is <strong>non-decreasing</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,2,5,3,5]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>One way to achieve the maximum size is:</p> <ol> <li>Replace subarray <code>nums[1..2] = [2, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 3, 5]</code>.</li> <li>Replace subarray <code>nums[2..3] = [3, 5]</code> with <code>5</code> &rarr; <code>[4, 5, 5]</code>.</li> </ol> <p>The final array <code>[4, 5, 5]</code> is non-decreasing with size <font face="monospace">3.</font></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>No operation is needed as the array <code>[1,2,3]</code> is already non-decreasing.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 2 * 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 2 * 10<sup>5</sup></code></li> </ul>
Stack; Greedy; Array; Monotonic Stack
TypeScript
function maximumPossibleSize(nums: number[]): number { let [ans, mx] = [0, 0]; for (const x of nums) { if (mx <= x) { ++ans; mx = x; } } return ans; }
3,527
Find the Most Common Response
Medium
<p>You are given a 2D string array <code>responses</code> where each <code>responses[i]</code> is an array of strings representing survey responses from the <code>i<sup>th</sup></code> day.</p> <p>Return the <strong>most common</strong> response across all days after removing <strong>duplicate</strong> responses within each <code>responses[i]</code>. If there is a tie, return the <em><span data-keyword="lexicographically-smaller-string">lexicographically smallest</span></em> response.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;,&quot;ok&quot;],[&quot;ok&quot;,&quot;bad&quot;,&quot;good&quot;,&quot;ok&quot;,&quot;ok&quot;],[&quot;good&quot;],[&quot;bad&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;good&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list, <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;, &quot;good&quot;], [&quot;good&quot;], [&quot;bad&quot;]]</code>.</li> <li><code>&quot;good&quot;</code> appears 3 times, <code>&quot;ok&quot;</code> appears 2 times, and <code>&quot;bad&quot;</code> appears 2 times.</li> <li>Return <code>&quot;good&quot;</code> because it has the highest frequency.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;],[&quot;ok&quot;,&quot;bad&quot;],[&quot;bad&quot;,&quot;notsure&quot;],[&quot;great&quot;,&quot;good&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bad&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list we have <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;], [&quot;bad&quot;, &quot;notsure&quot;], [&quot;great&quot;, &quot;good&quot;]]</code>.</li> <li><code>&quot;bad&quot;</code>, <code>&quot;good&quot;</code>, and <code>&quot;ok&quot;</code> each occur 2 times.</li> <li>The output is <code>&quot;bad&quot;</code> because it is the lexicographically smallest amongst the words with the highest frequency.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= responses.length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i].length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i][j].length &lt;= 10</code></li> <li><code>responses[i][j]</code> consists of only lowercase English letters</li> </ul>
Array; Hash Table; String; Counting
C++
class Solution { public: string findCommonResponse(vector<vector<string>>& responses) { unordered_map<string, int> cnt; for (const auto& ws : responses) { unordered_set<string> s; for (const auto& w : ws) { if (s.insert(w).second) { ++cnt[w]; } } } string ans = responses[0][0]; for (const auto& e : cnt) { const string& w = e.first; int v = e.second; if (cnt[ans] < v || (cnt[ans] == v && w < ans)) { ans = w; } } return ans; } };
3,527
Find the Most Common Response
Medium
<p>You are given a 2D string array <code>responses</code> where each <code>responses[i]</code> is an array of strings representing survey responses from the <code>i<sup>th</sup></code> day.</p> <p>Return the <strong>most common</strong> response across all days after removing <strong>duplicate</strong> responses within each <code>responses[i]</code>. If there is a tie, return the <em><span data-keyword="lexicographically-smaller-string">lexicographically smallest</span></em> response.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;,&quot;ok&quot;],[&quot;ok&quot;,&quot;bad&quot;,&quot;good&quot;,&quot;ok&quot;,&quot;ok&quot;],[&quot;good&quot;],[&quot;bad&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;good&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list, <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;, &quot;good&quot;], [&quot;good&quot;], [&quot;bad&quot;]]</code>.</li> <li><code>&quot;good&quot;</code> appears 3 times, <code>&quot;ok&quot;</code> appears 2 times, and <code>&quot;bad&quot;</code> appears 2 times.</li> <li>Return <code>&quot;good&quot;</code> because it has the highest frequency.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;],[&quot;ok&quot;,&quot;bad&quot;],[&quot;bad&quot;,&quot;notsure&quot;],[&quot;great&quot;,&quot;good&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bad&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list we have <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;], [&quot;bad&quot;, &quot;notsure&quot;], [&quot;great&quot;, &quot;good&quot;]]</code>.</li> <li><code>&quot;bad&quot;</code>, <code>&quot;good&quot;</code>, and <code>&quot;ok&quot;</code> each occur 2 times.</li> <li>The output is <code>&quot;bad&quot;</code> because it is the lexicographically smallest amongst the words with the highest frequency.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= responses.length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i].length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i][j].length &lt;= 10</code></li> <li><code>responses[i][j]</code> consists of only lowercase English letters</li> </ul>
Array; Hash Table; String; Counting
Go
func findCommonResponse(responses [][]string) string { cnt := map[string]int{} for _, ws := range responses { s := map[string]struct{}{} for _, w := range ws { if _, ok := s[w]; !ok { s[w] = struct{}{} cnt[w]++ } } } ans := responses[0][0] for w, v := range cnt { if cnt[ans] < v || (cnt[ans] == v && w < ans) { ans = w } } return ans }
3,527
Find the Most Common Response
Medium
<p>You are given a 2D string array <code>responses</code> where each <code>responses[i]</code> is an array of strings representing survey responses from the <code>i<sup>th</sup></code> day.</p> <p>Return the <strong>most common</strong> response across all days after removing <strong>duplicate</strong> responses within each <code>responses[i]</code>. If there is a tie, return the <em><span data-keyword="lexicographically-smaller-string">lexicographically smallest</span></em> response.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;,&quot;ok&quot;],[&quot;ok&quot;,&quot;bad&quot;,&quot;good&quot;,&quot;ok&quot;,&quot;ok&quot;],[&quot;good&quot;],[&quot;bad&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;good&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list, <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;, &quot;good&quot;], [&quot;good&quot;], [&quot;bad&quot;]]</code>.</li> <li><code>&quot;good&quot;</code> appears 3 times, <code>&quot;ok&quot;</code> appears 2 times, and <code>&quot;bad&quot;</code> appears 2 times.</li> <li>Return <code>&quot;good&quot;</code> because it has the highest frequency.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;],[&quot;ok&quot;,&quot;bad&quot;],[&quot;bad&quot;,&quot;notsure&quot;],[&quot;great&quot;,&quot;good&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bad&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list we have <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;], [&quot;bad&quot;, &quot;notsure&quot;], [&quot;great&quot;, &quot;good&quot;]]</code>.</li> <li><code>&quot;bad&quot;</code>, <code>&quot;good&quot;</code>, and <code>&quot;ok&quot;</code> each occur 2 times.</li> <li>The output is <code>&quot;bad&quot;</code> because it is the lexicographically smallest amongst the words with the highest frequency.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= responses.length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i].length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i][j].length &lt;= 10</code></li> <li><code>responses[i][j]</code> consists of only lowercase English letters</li> </ul>
Array; Hash Table; String; Counting
Java
class Solution { public String findCommonResponse(List<List<String>> responses) { Map<String, Integer> cnt = new HashMap<>(); for (var ws : responses) { Set<String> s = new HashSet<>(); for (var w : ws) { if (s.add(w)) { cnt.merge(w, 1, Integer::sum); } } } String ans = responses.get(0).get(0); for (var e : cnt.entrySet()) { String w = e.getKey(); int v = e.getValue(); if (cnt.get(ans) < v || (cnt.get(ans) == v && w.compareTo(ans) < 0)) { ans = w; } } return ans; } }
3,527
Find the Most Common Response
Medium
<p>You are given a 2D string array <code>responses</code> where each <code>responses[i]</code> is an array of strings representing survey responses from the <code>i<sup>th</sup></code> day.</p> <p>Return the <strong>most common</strong> response across all days after removing <strong>duplicate</strong> responses within each <code>responses[i]</code>. If there is a tie, return the <em><span data-keyword="lexicographically-smaller-string">lexicographically smallest</span></em> response.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;,&quot;ok&quot;],[&quot;ok&quot;,&quot;bad&quot;,&quot;good&quot;,&quot;ok&quot;,&quot;ok&quot;],[&quot;good&quot;],[&quot;bad&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;good&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list, <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;, &quot;good&quot;], [&quot;good&quot;], [&quot;bad&quot;]]</code>.</li> <li><code>&quot;good&quot;</code> appears 3 times, <code>&quot;ok&quot;</code> appears 2 times, and <code>&quot;bad&quot;</code> appears 2 times.</li> <li>Return <code>&quot;good&quot;</code> because it has the highest frequency.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;],[&quot;ok&quot;,&quot;bad&quot;],[&quot;bad&quot;,&quot;notsure&quot;],[&quot;great&quot;,&quot;good&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bad&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list we have <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;], [&quot;bad&quot;, &quot;notsure&quot;], [&quot;great&quot;, &quot;good&quot;]]</code>.</li> <li><code>&quot;bad&quot;</code>, <code>&quot;good&quot;</code>, and <code>&quot;ok&quot;</code> each occur 2 times.</li> <li>The output is <code>&quot;bad&quot;</code> because it is the lexicographically smallest amongst the words with the highest frequency.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= responses.length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i].length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i][j].length &lt;= 10</code></li> <li><code>responses[i][j]</code> consists of only lowercase English letters</li> </ul>
Array; Hash Table; String; Counting
Python
class Solution: def findCommonResponse(self, responses: List[List[str]]) -> str: cnt = Counter() for ws in responses: for w in set(ws): cnt[w] += 1 ans = responses[0][0] for w, x in cnt.items(): if cnt[ans] < x or (cnt[ans] == x and w < ans): ans = w return ans
3,527
Find the Most Common Response
Medium
<p>You are given a 2D string array <code>responses</code> where each <code>responses[i]</code> is an array of strings representing survey responses from the <code>i<sup>th</sup></code> day.</p> <p>Return the <strong>most common</strong> response across all days after removing <strong>duplicate</strong> responses within each <code>responses[i]</code>. If there is a tie, return the <em><span data-keyword="lexicographically-smaller-string">lexicographically smallest</span></em> response.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;,&quot;ok&quot;],[&quot;ok&quot;,&quot;bad&quot;,&quot;good&quot;,&quot;ok&quot;,&quot;ok&quot;],[&quot;good&quot;],[&quot;bad&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;good&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list, <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;, &quot;good&quot;], [&quot;good&quot;], [&quot;bad&quot;]]</code>.</li> <li><code>&quot;good&quot;</code> appears 3 times, <code>&quot;ok&quot;</code> appears 2 times, and <code>&quot;bad&quot;</code> appears 2 times.</li> <li>Return <code>&quot;good&quot;</code> because it has the highest frequency.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">responses = [[&quot;good&quot;,&quot;ok&quot;,&quot;good&quot;],[&quot;ok&quot;,&quot;bad&quot;],[&quot;bad&quot;,&quot;notsure&quot;],[&quot;great&quot;,&quot;good&quot;]]</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bad&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>After removing duplicates within each list we have <code>responses = [[&quot;good&quot;, &quot;ok&quot;], [&quot;ok&quot;, &quot;bad&quot;], [&quot;bad&quot;, &quot;notsure&quot;], [&quot;great&quot;, &quot;good&quot;]]</code>.</li> <li><code>&quot;bad&quot;</code>, <code>&quot;good&quot;</code>, and <code>&quot;ok&quot;</code> each occur 2 times.</li> <li>The output is <code>&quot;bad&quot;</code> because it is the lexicographically smallest amongst the words with the highest frequency.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= responses.length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i].length &lt;= 1000</code></li> <li><code>1 &lt;= responses[i][j].length &lt;= 10</code></li> <li><code>responses[i][j]</code> consists of only lowercase English letters</li> </ul>
Array; Hash Table; String; Counting
TypeScript
function findCommonResponse(responses: string[][]): string { const cnt = new Map<string, number>(); for (const ws of responses) { const s = new Set<string>(); for (const w of ws) { if (!s.has(w)) { s.add(w); cnt.set(w, (cnt.get(w) ?? 0) + 1); } } } let ans = responses[0][0]; for (const [w, v] of cnt) { const best = cnt.get(ans)!; if (best < v || (best === v && w < ans)) { ans = w; } } return ans; }
3,528
Unit Conversion I
Medium
<p>There are <code>n</code> types of units indexed from <code>0</code> to <code>n - 1</code>. You are given a 2D integer array <code>conversions</code> of length <code>n - 1</code>, where <code>conversions[i] = [sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub>]</code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.</p> <p>Return an array <code>baseUnitConversion</code> of length <code>n</code>, where <code>baseUnitConversion[i]</code> is the number of units of type <code>i</code> equivalent to a single unit of type 0. Since the answer may be large, return each <code>baseUnitConversion[i]</code> <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[1,2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,6]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 2 using <code>conversions[0]</code>, then <code>conversions[1]</code>.</li> </ul> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3528.Unit%20Conversion%20I/images/example1.png" style="width: 545px; height: 118px;" /></div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[0,2,3],[1,3,4],[1,4,5],[2,5,2],[4,6,3],[5,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,8,10,6,30,24]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 3 units of type 2 using <code>conversions[1]</code>.</li> <li>Convert a single unit of type 0 into 8 units of type 3 using <code>conversions[0]</code>, then <code>conversions[2]</code>.</li> <li>Convert a single unit of type 0 into 10 units of type 4 using <code>conversions[0]</code>, then <code>conversions[3]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 5 using <code>conversions[1]</code>, then <code>conversions[4]</code>.</li> <li>Convert a single unit of type 0 into 30 units of type 6 using <code>conversions[0]</code>, <code>conversions[3]</code>, then <code>conversions[5]</code>.</li> <li>Convert a single unit of type 0 into 24 units of type 7 using <code>conversions[1]</code>, <code>conversions[4]</code>, then <code>conversions[6]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>conversions.length == n - 1</code></li> <li><code>0 &lt;= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub> &lt; n</code></li> <li><code>1 &lt;= conversionFactor<sub>i</sub> &lt;= 10<sup>9</sup></code></li> <li>It is guaranteed that unit 0 can be converted into any other unit through a <strong>unique</strong> combination of conversions without using any conversions in the opposite direction.</li> </ul>
Depth-First Search; Breadth-First Search; Graph
C++
class Solution { public: vector<int> baseUnitConversions(vector<vector<int>>& conversions) { const int mod = 1e9 + 7; int n = conversions.size() + 1; vector<vector<pair<int, int>>> g(n); vector<int> ans(n); for (const auto& e : conversions) { g[e[0]].push_back({e[1], e[2]}); } auto dfs = [&](this auto&& dfs, int s, long long mul) -> void { ans[s] = mul; for (auto [t, w] : g[s]) { dfs(t, mul * w % mod); } }; dfs(0, 1); return ans; } };
3,528
Unit Conversion I
Medium
<p>There are <code>n</code> types of units indexed from <code>0</code> to <code>n - 1</code>. You are given a 2D integer array <code>conversions</code> of length <code>n - 1</code>, where <code>conversions[i] = [sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub>]</code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.</p> <p>Return an array <code>baseUnitConversion</code> of length <code>n</code>, where <code>baseUnitConversion[i]</code> is the number of units of type <code>i</code> equivalent to a single unit of type 0. Since the answer may be large, return each <code>baseUnitConversion[i]</code> <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[1,2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,6]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 2 using <code>conversions[0]</code>, then <code>conversions[1]</code>.</li> </ul> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3528.Unit%20Conversion%20I/images/example1.png" style="width: 545px; height: 118px;" /></div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[0,2,3],[1,3,4],[1,4,5],[2,5,2],[4,6,3],[5,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,8,10,6,30,24]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 3 units of type 2 using <code>conversions[1]</code>.</li> <li>Convert a single unit of type 0 into 8 units of type 3 using <code>conversions[0]</code>, then <code>conversions[2]</code>.</li> <li>Convert a single unit of type 0 into 10 units of type 4 using <code>conversions[0]</code>, then <code>conversions[3]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 5 using <code>conversions[1]</code>, then <code>conversions[4]</code>.</li> <li>Convert a single unit of type 0 into 30 units of type 6 using <code>conversions[0]</code>, <code>conversions[3]</code>, then <code>conversions[5]</code>.</li> <li>Convert a single unit of type 0 into 24 units of type 7 using <code>conversions[1]</code>, <code>conversions[4]</code>, then <code>conversions[6]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>conversions.length == n - 1</code></li> <li><code>0 &lt;= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub> &lt; n</code></li> <li><code>1 &lt;= conversionFactor<sub>i</sub> &lt;= 10<sup>9</sup></code></li> <li>It is guaranteed that unit 0 can be converted into any other unit through a <strong>unique</strong> combination of conversions without using any conversions in the opposite direction.</li> </ul>
Depth-First Search; Breadth-First Search; Graph
Go
func baseUnitConversions(conversions [][]int) []int { const mod = int(1e9 + 7) n := len(conversions) + 1 g := make([][]struct{ t, w int }, n) for _, e := range conversions { s, t, w := e[0], e[1], e[2] g[s] = append(g[s], struct{ t, w int }{t, w}) } ans := make([]int, n) var dfs func(s int, mul int) dfs = func(s int, mul int) { ans[s] = mul for _, e := range g[s] { dfs(e.t, mul*e.w%mod) } } dfs(0, 1) return ans }
3,528
Unit Conversion I
Medium
<p>There are <code>n</code> types of units indexed from <code>0</code> to <code>n - 1</code>. You are given a 2D integer array <code>conversions</code> of length <code>n - 1</code>, where <code>conversions[i] = [sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub>]</code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.</p> <p>Return an array <code>baseUnitConversion</code> of length <code>n</code>, where <code>baseUnitConversion[i]</code> is the number of units of type <code>i</code> equivalent to a single unit of type 0. Since the answer may be large, return each <code>baseUnitConversion[i]</code> <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[1,2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,6]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 2 using <code>conversions[0]</code>, then <code>conversions[1]</code>.</li> </ul> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3528.Unit%20Conversion%20I/images/example1.png" style="width: 545px; height: 118px;" /></div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[0,2,3],[1,3,4],[1,4,5],[2,5,2],[4,6,3],[5,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,8,10,6,30,24]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 3 units of type 2 using <code>conversions[1]</code>.</li> <li>Convert a single unit of type 0 into 8 units of type 3 using <code>conversions[0]</code>, then <code>conversions[2]</code>.</li> <li>Convert a single unit of type 0 into 10 units of type 4 using <code>conversions[0]</code>, then <code>conversions[3]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 5 using <code>conversions[1]</code>, then <code>conversions[4]</code>.</li> <li>Convert a single unit of type 0 into 30 units of type 6 using <code>conversions[0]</code>, <code>conversions[3]</code>, then <code>conversions[5]</code>.</li> <li>Convert a single unit of type 0 into 24 units of type 7 using <code>conversions[1]</code>, <code>conversions[4]</code>, then <code>conversions[6]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>conversions.length == n - 1</code></li> <li><code>0 &lt;= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub> &lt; n</code></li> <li><code>1 &lt;= conversionFactor<sub>i</sub> &lt;= 10<sup>9</sup></code></li> <li>It is guaranteed that unit 0 can be converted into any other unit through a <strong>unique</strong> combination of conversions without using any conversions in the opposite direction.</li> </ul>
Depth-First Search; Breadth-First Search; Graph
Java
class Solution { private final int mod = (int) 1e9 + 7; private List<int[]>[] g; private int[] ans; private int n; public int[] baseUnitConversions(int[][] conversions) { n = conversions.length + 1; g = new List[n]; Arrays.setAll(g, k -> new ArrayList<>()); ans = new int[n]; for (var e : conversions) { g[e[0]].add(new int[] {e[1], e[2]}); } dfs(0, 1); return ans; } private void dfs(int s, long mul) { ans[s] = (int) mul; for (var e : g[s]) { dfs(e[0], mul * e[1] % mod); } } }
3,528
Unit Conversion I
Medium
<p>There are <code>n</code> types of units indexed from <code>0</code> to <code>n - 1</code>. You are given a 2D integer array <code>conversions</code> of length <code>n - 1</code>, where <code>conversions[i] = [sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub>]</code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.</p> <p>Return an array <code>baseUnitConversion</code> of length <code>n</code>, where <code>baseUnitConversion[i]</code> is the number of units of type <code>i</code> equivalent to a single unit of type 0. Since the answer may be large, return each <code>baseUnitConversion[i]</code> <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[1,2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,6]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 2 using <code>conversions[0]</code>, then <code>conversions[1]</code>.</li> </ul> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3528.Unit%20Conversion%20I/images/example1.png" style="width: 545px; height: 118px;" /></div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[0,2,3],[1,3,4],[1,4,5],[2,5,2],[4,6,3],[5,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,8,10,6,30,24]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 3 units of type 2 using <code>conversions[1]</code>.</li> <li>Convert a single unit of type 0 into 8 units of type 3 using <code>conversions[0]</code>, then <code>conversions[2]</code>.</li> <li>Convert a single unit of type 0 into 10 units of type 4 using <code>conversions[0]</code>, then <code>conversions[3]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 5 using <code>conversions[1]</code>, then <code>conversions[4]</code>.</li> <li>Convert a single unit of type 0 into 30 units of type 6 using <code>conversions[0]</code>, <code>conversions[3]</code>, then <code>conversions[5]</code>.</li> <li>Convert a single unit of type 0 into 24 units of type 7 using <code>conversions[1]</code>, <code>conversions[4]</code>, then <code>conversions[6]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>conversions.length == n - 1</code></li> <li><code>0 &lt;= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub> &lt; n</code></li> <li><code>1 &lt;= conversionFactor<sub>i</sub> &lt;= 10<sup>9</sup></code></li> <li>It is guaranteed that unit 0 can be converted into any other unit through a <strong>unique</strong> combination of conversions without using any conversions in the opposite direction.</li> </ul>
Depth-First Search; Breadth-First Search; Graph
Python
class Solution: def baseUnitConversions(self, conversions: List[List[int]]) -> List[int]: def dfs(s: int, mul: int) -> None: ans[s] = mul for t, w in g[s]: dfs(t, mul * w % mod) mod = 10**9 + 7 n = len(conversions) + 1 g = [[] for _ in range(n)] for s, t, w in conversions: g[s].append((t, w)) ans = [0] * n dfs(0, 1) return ans
3,528
Unit Conversion I
Medium
<p>There are <code>n</code> types of units indexed from <code>0</code> to <code>n - 1</code>. You are given a 2D integer array <code>conversions</code> of length <code>n - 1</code>, where <code>conversions[i] = [sourceUnit<sub>i</sub>, targetUnit<sub>i</sub>, conversionFactor<sub>i</sub>]</code>. This indicates that a single unit of type <code>sourceUnit<sub>i</sub></code> is equivalent to <code>conversionFactor<sub>i</sub></code> units of type <code>targetUnit<sub>i</sub></code>.</p> <p>Return an array <code>baseUnitConversion</code> of length <code>n</code>, where <code>baseUnitConversion[i]</code> is the number of units of type <code>i</code> equivalent to a single unit of type 0. Since the answer may be large, return each <code>baseUnitConversion[i]</code> <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[1,2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,6]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 2 using <code>conversions[0]</code>, then <code>conversions[1]</code>.</li> </ul> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3528.Unit%20Conversion%20I/images/example1.png" style="width: 545px; height: 118px;" /></div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">conversions = [[0,1,2],[0,2,3],[1,3,4],[1,4,5],[2,5,2],[4,6,3],[5,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,8,10,6,30,24]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Convert a single unit of type 0 into 2 units of type 1 using <code>conversions[0]</code>.</li> <li>Convert a single unit of type 0 into 3 units of type 2 using <code>conversions[1]</code>.</li> <li>Convert a single unit of type 0 into 8 units of type 3 using <code>conversions[0]</code>, then <code>conversions[2]</code>.</li> <li>Convert a single unit of type 0 into 10 units of type 4 using <code>conversions[0]</code>, then <code>conversions[3]</code>.</li> <li>Convert a single unit of type 0 into 6 units of type 5 using <code>conversions[1]</code>, then <code>conversions[4]</code>.</li> <li>Convert a single unit of type 0 into 30 units of type 6 using <code>conversions[0]</code>, <code>conversions[3]</code>, then <code>conversions[5]</code>.</li> <li>Convert a single unit of type 0 into 24 units of type 7 using <code>conversions[1]</code>, <code>conversions[4]</code>, then <code>conversions[6]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>conversions.length == n - 1</code></li> <li><code>0 &lt;= sourceUnit<sub>i</sub>, targetUnit<sub>i</sub> &lt; n</code></li> <li><code>1 &lt;= conversionFactor<sub>i</sub> &lt;= 10<sup>9</sup></code></li> <li>It is guaranteed that unit 0 can be converted into any other unit through a <strong>unique</strong> combination of conversions without using any conversions in the opposite direction.</li> </ul>
Depth-First Search; Breadth-First Search; Graph
TypeScript
function baseUnitConversions(conversions: number[][]): number[] { const mod = BigInt(1e9 + 7); const n = conversions.length + 1; const g: { t: number; w: number }[][] = Array.from({ length: n }, () => []); for (const [s, t, w] of conversions) { g[s].push({ t, w }); } const ans: number[] = Array(n).fill(0); const dfs = (s: number, mul: number) => { ans[s] = mul; for (const { t, w } of g[s]) { dfs(t, Number((BigInt(mul) * BigInt(w)) % mod)); } }; dfs(0, 1); return ans; }
3,531
Count Covered Buildings
Medium
<p>You are given a positive integer <code>n</code>, representing an <code>n x n</code> city. You are also given a 2D grid <code>buildings</code>, where <code>buildings[i] = [x, y]</code> denotes a <strong>unique</strong> building located at coordinates <code>[x, y]</code>.</p> <p>A building is <strong>covered</strong> if there is at least one building in all <strong>four</strong> directions: left, right, above, and below.</p> <p>Return the number of <strong>covered</strong> buildings.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101085-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,2],[2,2],[3,2],[2,1],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[2,2]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,2]</code>)</li> <li>below (<code>[3,2]</code>)</li> <li>left (<code>[2,1]</code>)</li> <li>right (<code>[2,3]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101086-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,1],[1,2],[2,1],[2,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>No building has at least one building in all four directions.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6248862251436067566-x.jpg" style="width: 202px; height: 205px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, buildings = [[1,3],[3,2],[3,3],[3,5],[5,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[3,3]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,3]</code>)</li> <li>below (<code>[5,3]</code>)</li> <li>left (<code>[3,2]</code>)</li> <li>right (<code>[3,5]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= buildings.length &lt;= 10<sup>5</sup> </code></li> <li><code>buildings[i] = [x, y]</code></li> <li><code>1 &lt;= x, y &lt;= n</code></li> <li>All coordinates of <code>buildings</code> are <strong>unique</strong>.</li> </ul>
Array; Hash Table; Sorting
C++
class Solution { public: int countCoveredBuildings(int n, vector<vector<int>>& buildings) { unordered_map<int, vector<int>> g1; unordered_map<int, vector<int>> g2; for (const auto& building : buildings) { int x = building[0], y = building[1]; g1[x].push_back(y); g2[y].push_back(x); } for (auto& e : g1) { sort(e.second.begin(), e.second.end()); } for (auto& e : g2) { sort(e.second.begin(), e.second.end()); } int ans = 0; for (const auto& building : buildings) { int x = building[0], y = building[1]; const vector<int>& l1 = g1[x]; const vector<int>& l2 = g2[y]; if (l2[0] < x && x < l2[l2.size() - 1] && l1[0] < y && y < l1[l1.size() - 1]) { ans++; } } return ans; } };
3,531
Count Covered Buildings
Medium
<p>You are given a positive integer <code>n</code>, representing an <code>n x n</code> city. You are also given a 2D grid <code>buildings</code>, where <code>buildings[i] = [x, y]</code> denotes a <strong>unique</strong> building located at coordinates <code>[x, y]</code>.</p> <p>A building is <strong>covered</strong> if there is at least one building in all <strong>four</strong> directions: left, right, above, and below.</p> <p>Return the number of <strong>covered</strong> buildings.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101085-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,2],[2,2],[3,2],[2,1],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[2,2]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,2]</code>)</li> <li>below (<code>[3,2]</code>)</li> <li>left (<code>[2,1]</code>)</li> <li>right (<code>[2,3]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101086-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,1],[1,2],[2,1],[2,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>No building has at least one building in all four directions.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6248862251436067566-x.jpg" style="width: 202px; height: 205px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, buildings = [[1,3],[3,2],[3,3],[3,5],[5,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[3,3]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,3]</code>)</li> <li>below (<code>[5,3]</code>)</li> <li>left (<code>[3,2]</code>)</li> <li>right (<code>[3,5]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= buildings.length &lt;= 10<sup>5</sup> </code></li> <li><code>buildings[i] = [x, y]</code></li> <li><code>1 &lt;= x, y &lt;= n</code></li> <li>All coordinates of <code>buildings</code> are <strong>unique</strong>.</li> </ul>
Array; Hash Table; Sorting
Go
func countCoveredBuildings(n int, buildings [][]int) (ans int) { g1 := make(map[int][]int) g2 := make(map[int][]int) for _, building := range buildings { x, y := building[0], building[1] g1[x] = append(g1[x], y) g2[y] = append(g2[y], x) } for _, list := range g1 { sort.Ints(list) } for _, list := range g2 { sort.Ints(list) } for _, building := range buildings { x, y := building[0], building[1] l1 := g1[x] l2 := g2[y] if l2[0] < x && x < l2[len(l2)-1] && l1[0] < y && y < l1[len(l1)-1] { ans++ } } return }
3,531
Count Covered Buildings
Medium
<p>You are given a positive integer <code>n</code>, representing an <code>n x n</code> city. You are also given a 2D grid <code>buildings</code>, where <code>buildings[i] = [x, y]</code> denotes a <strong>unique</strong> building located at coordinates <code>[x, y]</code>.</p> <p>A building is <strong>covered</strong> if there is at least one building in all <strong>four</strong> directions: left, right, above, and below.</p> <p>Return the number of <strong>covered</strong> buildings.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101085-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,2],[2,2],[3,2],[2,1],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[2,2]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,2]</code>)</li> <li>below (<code>[3,2]</code>)</li> <li>left (<code>[2,1]</code>)</li> <li>right (<code>[2,3]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101086-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,1],[1,2],[2,1],[2,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>No building has at least one building in all four directions.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6248862251436067566-x.jpg" style="width: 202px; height: 205px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, buildings = [[1,3],[3,2],[3,3],[3,5],[5,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[3,3]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,3]</code>)</li> <li>below (<code>[5,3]</code>)</li> <li>left (<code>[3,2]</code>)</li> <li>right (<code>[3,5]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= buildings.length &lt;= 10<sup>5</sup> </code></li> <li><code>buildings[i] = [x, y]</code></li> <li><code>1 &lt;= x, y &lt;= n</code></li> <li>All coordinates of <code>buildings</code> are <strong>unique</strong>.</li> </ul>
Array; Hash Table; Sorting
Java
class Solution { public int countCoveredBuildings(int n, int[][] buildings) { Map<Integer, List<Integer>> g1 = new HashMap<>(); Map<Integer, List<Integer>> g2 = new HashMap<>(); for (int[] building : buildings) { int x = building[0], y = building[1]; g1.computeIfAbsent(x, k -> new ArrayList<>()).add(y); g2.computeIfAbsent(y, k -> new ArrayList<>()).add(x); } for (var e : g1.entrySet()) { Collections.sort(e.getValue()); } for (var e : g2.entrySet()) { Collections.sort(e.getValue()); } int ans = 0; for (int[] building : buildings) { int x = building[0], y = building[1]; List<Integer> l1 = g1.get(x); List<Integer> l2 = g2.get(y); if (l2.get(0) < x && x < l2.get(l2.size() - 1) && l1.get(0) < y && y < l1.get(l1.size() - 1)) { ans++; } } return ans; } }
3,531
Count Covered Buildings
Medium
<p>You are given a positive integer <code>n</code>, representing an <code>n x n</code> city. You are also given a 2D grid <code>buildings</code>, where <code>buildings[i] = [x, y]</code> denotes a <strong>unique</strong> building located at coordinates <code>[x, y]</code>.</p> <p>A building is <strong>covered</strong> if there is at least one building in all <strong>four</strong> directions: left, right, above, and below.</p> <p>Return the number of <strong>covered</strong> buildings.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101085-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,2],[2,2],[3,2],[2,1],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[2,2]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,2]</code>)</li> <li>below (<code>[3,2]</code>)</li> <li>left (<code>[2,1]</code>)</li> <li>right (<code>[2,3]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101086-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,1],[1,2],[2,1],[2,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>No building has at least one building in all four directions.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6248862251436067566-x.jpg" style="width: 202px; height: 205px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, buildings = [[1,3],[3,2],[3,3],[3,5],[5,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[3,3]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,3]</code>)</li> <li>below (<code>[5,3]</code>)</li> <li>left (<code>[3,2]</code>)</li> <li>right (<code>[3,5]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= buildings.length &lt;= 10<sup>5</sup> </code></li> <li><code>buildings[i] = [x, y]</code></li> <li><code>1 &lt;= x, y &lt;= n</code></li> <li>All coordinates of <code>buildings</code> are <strong>unique</strong>.</li> </ul>
Array; Hash Table; Sorting
Python
class Solution: def countCoveredBuildings(self, n: int, buildings: List[List[int]]) -> int: g1 = defaultdict(list) g2 = defaultdict(list) for x, y in buildings: g1[x].append(y) g2[y].append(x) for x in g1: g1[x].sort() for y in g2: g2[y].sort() ans = 0 for x, y in buildings: l1 = g1[x] l2 = g2[y] if l2[0] < x < l2[-1] and l1[0] < y < l1[-1]: ans += 1 return ans
3,531
Count Covered Buildings
Medium
<p>You are given a positive integer <code>n</code>, representing an <code>n x n</code> city. You are also given a 2D grid <code>buildings</code>, where <code>buildings[i] = [x, y]</code> denotes a <strong>unique</strong> building located at coordinates <code>[x, y]</code>.</p> <p>A building is <strong>covered</strong> if there is at least one building in all <strong>four</strong> directions: left, right, above, and below.</p> <p>Return the number of <strong>covered</strong> buildings.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101085-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,2],[2,2],[3,2],[2,1],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[2,2]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,2]</code>)</li> <li>below (<code>[3,2]</code>)</li> <li>left (<code>[2,1]</code>)</li> <li>right (<code>[2,3]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6212982906394101086-m.jpg" style="width: 200px; height: 204px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, buildings = [[1,1],[1,2],[2,1],[2,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>No building has at least one building in all four directions.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <p><img src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3531.Count%20Covered%20Buildings/images/telegram-cloud-photo-size-5-6248862251436067566-x.jpg" style="width: 202px; height: 205px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, buildings = [[1,3],[3,2],[3,3],[3,5],[5,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Only building <code>[3,3]</code> is covered as it has at least one building: <ul> <li>above (<code>[1,3]</code>)</li> <li>below (<code>[5,3]</code>)</li> <li>left (<code>[3,2]</code>)</li> <li>right (<code>[3,5]</code>)</li> </ul> </li> <li>Thus, the count of covered buildings is 1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= buildings.length &lt;= 10<sup>5</sup> </code></li> <li><code>buildings[i] = [x, y]</code></li> <li><code>1 &lt;= x, y &lt;= n</code></li> <li>All coordinates of <code>buildings</code> are <strong>unique</strong>.</li> </ul>
Array; Hash Table; Sorting
TypeScript
function countCoveredBuildings(n: number, buildings: number[][]): number { const g1: Map<number, number[]> = new Map(); const g2: Map<number, number[]> = new Map(); for (const [x, y] of buildings) { if (!g1.has(x)) g1.set(x, []); g1.get(x)?.push(y); if (!g2.has(y)) g2.set(y, []); g2.get(y)?.push(x); } for (const list of g1.values()) { list.sort((a, b) => a - b); } for (const list of g2.values()) { list.sort((a, b) => a - b); } let ans = 0; for (const [x, y] of buildings) { const l1 = g1.get(x)!; const l2 = g2.get(y)!; if (l2[0] < x && x < l2[l2.length - 1] && l1[0] < y && y < l1[l1.length - 1]) { ans++; } } return ans; }
3,532
Path Existence Queries in a Graph I
Medium
<p>You are given an integer <code>n</code> representing the number of nodes in a graph, labeled from 0 to <code>n - 1</code>.</p> <p>You are also given an integer array <code>nums</code> of length <code>n</code> sorted in <strong>non-decreasing</strong> order, and an integer <code>maxDiff</code>.</p> <p>An <strong>undirected </strong>edge exists between nodes <code>i</code> and <code>j</code> if the <strong>absolute</strong> difference between <code>nums[i]</code> and <code>nums[j]</code> is <strong>at most</strong> <code>maxDiff</code> (i.e., <code>|nums[i] - nums[j]| &lt;= maxDiff</code>).</p> <p>You are also given a 2D integer array <code>queries</code>. For each <code>queries[i] = [u<sub>i</sub>, v<sub>i</sub>]</code>, determine whether there exists a path between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code>.</p> <p>Return a boolean array <code>answer</code>, where <code>answer[i]</code> is <code>true</code> if there exists a path between <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the <code>i<sup>th</sup></code> query and <code>false</code> otherwise.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, nums = [1,3], maxDiff = 1, queries = [[0,0],[0,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">[true,false]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Query <code>[0,0]</code>: Node 0 has a trivial path to itself.</li> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |1 - 3| = 2</code>, which is greater than <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[true, false]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, nums = [2,5,6,8], maxDiff = 2, queries = [[0,1],[0,2],[1,3],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,false,true,true]</span></p> <p><strong>Explanation:</strong></p> <p>The resulting graph is:</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3532.Path%20Existence%20Queries%20in%20a%20Graph%20I/images/screenshot-2025-03-26-at-122249.png" style="width: 300px; height: 170px;" /></p> <ul> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |2 - 5| = 3</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[0,2]</code>: There is no edge between Node 0 and Node 2 because <code>|nums[0] - nums[2]| = |2 - 6| = 4</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[1,3]</code>: There is a path between Node 1 and Node 3 through Node 2 since <code>|nums[1] - nums[2]| = |5 - 6| = 1</code> and <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, both of which are within <code>maxDiff</code>.</li> <li>Query <code>[2,3]</code>: There is an edge between Node 2 and Node 3 because <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, which is equal to <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[false, false, true, true]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li> <li><code>0 &lt;= maxDiff &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [u<sub>i</sub>, v<sub>i</sub>]</code></li> <li><code>0 &lt;= u<sub>i</sub>, v<sub>i</sub> &lt; n</code></li> </ul>
Union Find; Graph; Array; Hash Table; Binary Search
C++
class Solution { public: vector<bool> pathExistenceQueries(int n, vector<int>& nums, int maxDiff, vector<vector<int>>& queries) { vector<int> g(n); int cnt = 0; for (int i = 1; i < n; ++i) { if (nums[i] - nums[i - 1] > maxDiff) { ++cnt; } g[i] = cnt; } vector<bool> ans; for (const auto& q : queries) { int u = q[0], v = q[1]; ans.push_back(g[u] == g[v]); } return ans; } };
3,532
Path Existence Queries in a Graph I
Medium
<p>You are given an integer <code>n</code> representing the number of nodes in a graph, labeled from 0 to <code>n - 1</code>.</p> <p>You are also given an integer array <code>nums</code> of length <code>n</code> sorted in <strong>non-decreasing</strong> order, and an integer <code>maxDiff</code>.</p> <p>An <strong>undirected </strong>edge exists between nodes <code>i</code> and <code>j</code> if the <strong>absolute</strong> difference between <code>nums[i]</code> and <code>nums[j]</code> is <strong>at most</strong> <code>maxDiff</code> (i.e., <code>|nums[i] - nums[j]| &lt;= maxDiff</code>).</p> <p>You are also given a 2D integer array <code>queries</code>. For each <code>queries[i] = [u<sub>i</sub>, v<sub>i</sub>]</code>, determine whether there exists a path between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code>.</p> <p>Return a boolean array <code>answer</code>, where <code>answer[i]</code> is <code>true</code> if there exists a path between <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the <code>i<sup>th</sup></code> query and <code>false</code> otherwise.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, nums = [1,3], maxDiff = 1, queries = [[0,0],[0,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">[true,false]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Query <code>[0,0]</code>: Node 0 has a trivial path to itself.</li> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |1 - 3| = 2</code>, which is greater than <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[true, false]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, nums = [2,5,6,8], maxDiff = 2, queries = [[0,1],[0,2],[1,3],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,false,true,true]</span></p> <p><strong>Explanation:</strong></p> <p>The resulting graph is:</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3532.Path%20Existence%20Queries%20in%20a%20Graph%20I/images/screenshot-2025-03-26-at-122249.png" style="width: 300px; height: 170px;" /></p> <ul> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |2 - 5| = 3</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[0,2]</code>: There is no edge between Node 0 and Node 2 because <code>|nums[0] - nums[2]| = |2 - 6| = 4</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[1,3]</code>: There is a path between Node 1 and Node 3 through Node 2 since <code>|nums[1] - nums[2]| = |5 - 6| = 1</code> and <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, both of which are within <code>maxDiff</code>.</li> <li>Query <code>[2,3]</code>: There is an edge between Node 2 and Node 3 because <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, which is equal to <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[false, false, true, true]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li> <li><code>0 &lt;= maxDiff &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [u<sub>i</sub>, v<sub>i</sub>]</code></li> <li><code>0 &lt;= u<sub>i</sub>, v<sub>i</sub> &lt; n</code></li> </ul>
Union Find; Graph; Array; Hash Table; Binary Search
Go
func pathExistenceQueries(n int, nums []int, maxDiff int, queries [][]int) (ans []bool) { g := make([]int, n) cnt := 0 for i := 1; i < n; i++ { if nums[i]-nums[i-1] > maxDiff { cnt++ } g[i] = cnt } for _, q := range queries { u, v := q[0], q[1] ans = append(ans, g[u] == g[v]) } return }
3,532
Path Existence Queries in a Graph I
Medium
<p>You are given an integer <code>n</code> representing the number of nodes in a graph, labeled from 0 to <code>n - 1</code>.</p> <p>You are also given an integer array <code>nums</code> of length <code>n</code> sorted in <strong>non-decreasing</strong> order, and an integer <code>maxDiff</code>.</p> <p>An <strong>undirected </strong>edge exists between nodes <code>i</code> and <code>j</code> if the <strong>absolute</strong> difference between <code>nums[i]</code> and <code>nums[j]</code> is <strong>at most</strong> <code>maxDiff</code> (i.e., <code>|nums[i] - nums[j]| &lt;= maxDiff</code>).</p> <p>You are also given a 2D integer array <code>queries</code>. For each <code>queries[i] = [u<sub>i</sub>, v<sub>i</sub>]</code>, determine whether there exists a path between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code>.</p> <p>Return a boolean array <code>answer</code>, where <code>answer[i]</code> is <code>true</code> if there exists a path between <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the <code>i<sup>th</sup></code> query and <code>false</code> otherwise.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, nums = [1,3], maxDiff = 1, queries = [[0,0],[0,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">[true,false]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Query <code>[0,0]</code>: Node 0 has a trivial path to itself.</li> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |1 - 3| = 2</code>, which is greater than <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[true, false]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, nums = [2,5,6,8], maxDiff = 2, queries = [[0,1],[0,2],[1,3],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,false,true,true]</span></p> <p><strong>Explanation:</strong></p> <p>The resulting graph is:</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3532.Path%20Existence%20Queries%20in%20a%20Graph%20I/images/screenshot-2025-03-26-at-122249.png" style="width: 300px; height: 170px;" /></p> <ul> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |2 - 5| = 3</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[0,2]</code>: There is no edge between Node 0 and Node 2 because <code>|nums[0] - nums[2]| = |2 - 6| = 4</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[1,3]</code>: There is a path between Node 1 and Node 3 through Node 2 since <code>|nums[1] - nums[2]| = |5 - 6| = 1</code> and <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, both of which are within <code>maxDiff</code>.</li> <li>Query <code>[2,3]</code>: There is an edge between Node 2 and Node 3 because <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, which is equal to <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[false, false, true, true]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li> <li><code>0 &lt;= maxDiff &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [u<sub>i</sub>, v<sub>i</sub>]</code></li> <li><code>0 &lt;= u<sub>i</sub>, v<sub>i</sub> &lt; n</code></li> </ul>
Union Find; Graph; Array; Hash Table; Binary Search
Java
class Solution { public boolean[] pathExistenceQueries(int n, int[] nums, int maxDiff, int[][] queries) { int[] g = new int[n]; int cnt = 0; for (int i = 1; i < n; ++i) { if (nums[i] - nums[i - 1] > maxDiff) { cnt++; } g[i] = cnt; } int m = queries.length; boolean[] ans = new boolean[m]; for (int i = 0; i < m; ++i) { int u = queries[i][0]; int v = queries[i][1]; ans[i] = g[u] == g[v]; } return ans; } }
3,532
Path Existence Queries in a Graph I
Medium
<p>You are given an integer <code>n</code> representing the number of nodes in a graph, labeled from 0 to <code>n - 1</code>.</p> <p>You are also given an integer array <code>nums</code> of length <code>n</code> sorted in <strong>non-decreasing</strong> order, and an integer <code>maxDiff</code>.</p> <p>An <strong>undirected </strong>edge exists between nodes <code>i</code> and <code>j</code> if the <strong>absolute</strong> difference between <code>nums[i]</code> and <code>nums[j]</code> is <strong>at most</strong> <code>maxDiff</code> (i.e., <code>|nums[i] - nums[j]| &lt;= maxDiff</code>).</p> <p>You are also given a 2D integer array <code>queries</code>. For each <code>queries[i] = [u<sub>i</sub>, v<sub>i</sub>]</code>, determine whether there exists a path between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code>.</p> <p>Return a boolean array <code>answer</code>, where <code>answer[i]</code> is <code>true</code> if there exists a path between <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the <code>i<sup>th</sup></code> query and <code>false</code> otherwise.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, nums = [1,3], maxDiff = 1, queries = [[0,0],[0,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">[true,false]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Query <code>[0,0]</code>: Node 0 has a trivial path to itself.</li> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |1 - 3| = 2</code>, which is greater than <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[true, false]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, nums = [2,5,6,8], maxDiff = 2, queries = [[0,1],[0,2],[1,3],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,false,true,true]</span></p> <p><strong>Explanation:</strong></p> <p>The resulting graph is:</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3532.Path%20Existence%20Queries%20in%20a%20Graph%20I/images/screenshot-2025-03-26-at-122249.png" style="width: 300px; height: 170px;" /></p> <ul> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |2 - 5| = 3</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[0,2]</code>: There is no edge between Node 0 and Node 2 because <code>|nums[0] - nums[2]| = |2 - 6| = 4</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[1,3]</code>: There is a path between Node 1 and Node 3 through Node 2 since <code>|nums[1] - nums[2]| = |5 - 6| = 1</code> and <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, both of which are within <code>maxDiff</code>.</li> <li>Query <code>[2,3]</code>: There is an edge between Node 2 and Node 3 because <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, which is equal to <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[false, false, true, true]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li> <li><code>0 &lt;= maxDiff &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [u<sub>i</sub>, v<sub>i</sub>]</code></li> <li><code>0 &lt;= u<sub>i</sub>, v<sub>i</sub> &lt; n</code></li> </ul>
Union Find; Graph; Array; Hash Table; Binary Search
Python
class Solution: def pathExistenceQueries( self, n: int, nums: List[int], maxDiff: int, queries: List[List[int]] ) -> List[bool]: g = [0] * n cnt = 0 for i in range(1, n): if nums[i] - nums[i - 1] > maxDiff: cnt += 1 g[i] = cnt return [g[u] == g[v] for u, v in queries]
3,532
Path Existence Queries in a Graph I
Medium
<p>You are given an integer <code>n</code> representing the number of nodes in a graph, labeled from 0 to <code>n - 1</code>.</p> <p>You are also given an integer array <code>nums</code> of length <code>n</code> sorted in <strong>non-decreasing</strong> order, and an integer <code>maxDiff</code>.</p> <p>An <strong>undirected </strong>edge exists between nodes <code>i</code> and <code>j</code> if the <strong>absolute</strong> difference between <code>nums[i]</code> and <code>nums[j]</code> is <strong>at most</strong> <code>maxDiff</code> (i.e., <code>|nums[i] - nums[j]| &lt;= maxDiff</code>).</p> <p>You are also given a 2D integer array <code>queries</code>. For each <code>queries[i] = [u<sub>i</sub>, v<sub>i</sub>]</code>, determine whether there exists a path between nodes <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code>.</p> <p>Return a boolean array <code>answer</code>, where <code>answer[i]</code> is <code>true</code> if there exists a path between <code>u<sub>i</sub></code> and <code>v<sub>i</sub></code> in the <code>i<sup>th</sup></code> query and <code>false</code> otherwise.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, nums = [1,3], maxDiff = 1, queries = [[0,0],[0,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">[true,false]</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Query <code>[0,0]</code>: Node 0 has a trivial path to itself.</li> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |1 - 3| = 2</code>, which is greater than <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[true, false]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, nums = [2,5,6,8], maxDiff = 2, queries = [[0,1],[0,2],[1,3],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,false,true,true]</span></p> <p><strong>Explanation:</strong></p> <p>The resulting graph is:</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3532.Path%20Existence%20Queries%20in%20a%20Graph%20I/images/screenshot-2025-03-26-at-122249.png" style="width: 300px; height: 170px;" /></p> <ul> <li>Query <code>[0,1]</code>: There is no edge between Node 0 and Node 1 because <code>|nums[0] - nums[1]| = |2 - 5| = 3</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[0,2]</code>: There is no edge between Node 0 and Node 2 because <code>|nums[0] - nums[2]| = |2 - 6| = 4</code>, which is greater than <code>maxDiff</code>.</li> <li>Query <code>[1,3]</code>: There is a path between Node 1 and Node 3 through Node 2 since <code>|nums[1] - nums[2]| = |5 - 6| = 1</code> and <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, both of which are within <code>maxDiff</code>.</li> <li>Query <code>[2,3]</code>: There is an edge between Node 2 and Node 3 because <code>|nums[2] - nums[3]| = |6 - 8| = 2</code>, which is equal to <code>maxDiff</code>.</li> <li>Thus, the final answer after processing all the queries is <code>[false, false, true, true]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>0 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>nums</code> is sorted in <strong>non-decreasing</strong> order.</li> <li><code>0 &lt;= maxDiff &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [u<sub>i</sub>, v<sub>i</sub>]</code></li> <li><code>0 &lt;= u<sub>i</sub>, v<sub>i</sub> &lt; n</code></li> </ul>
Union Find; Graph; Array; Hash Table; Binary Search
TypeScript
function pathExistenceQueries( n: number, nums: number[], maxDiff: number, queries: number[][], ): boolean[] { const g: number[] = Array(n).fill(0); let cnt = 0; for (let i = 1; i < n; ++i) { if (nums[i] - nums[i - 1] > maxDiff) { ++cnt; } g[i] = cnt; } return queries.map(([u, v]) => g[u] === g[v]); }
3,536
Maximum Product of Two Digits
Easy
<p>You are given a positive integer <code>n</code>.</p> <p>Return the <strong>maximum</strong> product of any two digits in <code>n</code>.</p> <p><strong>Note:</strong> You may use the <strong>same</strong> digit twice if it appears more than once in <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 31</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[3, 1]</code>.</li> <li>The possible products of any two digits are: <code>3 * 1 = 3</code>.</li> <li>The maximum product is 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 22</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[2, 2]</code>.</li> <li>The possible products of any two digits are: <code>2 * 2 = 4</code>.</li> <li>The maximum product is 4.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 124</span></p> <p><strong>Output:</strong> <span class="example-io">8</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[1, 2, 4]</code>.</li> <li>The possible products of any two digits are: <code>1 * 2 = 2</code>, <code>1 * 4 = 4</code>, <code>2 * 4 = 8</code>.</li> <li>The maximum product is 8.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>10 &lt;= n &lt;= 10<sup>9</sup></code></li> </ul>
Math; Sorting
C++
class Solution { public: int maxProduct(int n) { int a = 0, b = 0; for (; n; n /= 10) { int x = n % 10; if (a < x) { b = a; a = x; } else if (b < x) { b = x; } } return a * b; } };
3,536
Maximum Product of Two Digits
Easy
<p>You are given a positive integer <code>n</code>.</p> <p>Return the <strong>maximum</strong> product of any two digits in <code>n</code>.</p> <p><strong>Note:</strong> You may use the <strong>same</strong> digit twice if it appears more than once in <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 31</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[3, 1]</code>.</li> <li>The possible products of any two digits are: <code>3 * 1 = 3</code>.</li> <li>The maximum product is 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 22</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[2, 2]</code>.</li> <li>The possible products of any two digits are: <code>2 * 2 = 4</code>.</li> <li>The maximum product is 4.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 124</span></p> <p><strong>Output:</strong> <span class="example-io">8</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[1, 2, 4]</code>.</li> <li>The possible products of any two digits are: <code>1 * 2 = 2</code>, <code>1 * 4 = 4</code>, <code>2 * 4 = 8</code>.</li> <li>The maximum product is 8.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>10 &lt;= n &lt;= 10<sup>9</sup></code></li> </ul>
Math; Sorting
Go
func maxProduct(n int) int { a, b := 0, 0 for ; n > 0; n /= 10 { x := n % 10 if a < x { b, a = a, x } else if b < x { b = x } } return a * b }
3,536
Maximum Product of Two Digits
Easy
<p>You are given a positive integer <code>n</code>.</p> <p>Return the <strong>maximum</strong> product of any two digits in <code>n</code>.</p> <p><strong>Note:</strong> You may use the <strong>same</strong> digit twice if it appears more than once in <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 31</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[3, 1]</code>.</li> <li>The possible products of any two digits are: <code>3 * 1 = 3</code>.</li> <li>The maximum product is 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 22</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[2, 2]</code>.</li> <li>The possible products of any two digits are: <code>2 * 2 = 4</code>.</li> <li>The maximum product is 4.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 124</span></p> <p><strong>Output:</strong> <span class="example-io">8</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[1, 2, 4]</code>.</li> <li>The possible products of any two digits are: <code>1 * 2 = 2</code>, <code>1 * 4 = 4</code>, <code>2 * 4 = 8</code>.</li> <li>The maximum product is 8.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>10 &lt;= n &lt;= 10<sup>9</sup></code></li> </ul>
Math; Sorting
Java
class Solution { public int maxProduct(int n) { int a = 0, b = 0; for (; n > 0; n /= 10) { int x = n % 10; if (a < x) { b = a; a = x; } else if (b < x) { b = x; } } return a * b; } }
3,536
Maximum Product of Two Digits
Easy
<p>You are given a positive integer <code>n</code>.</p> <p>Return the <strong>maximum</strong> product of any two digits in <code>n</code>.</p> <p><strong>Note:</strong> You may use the <strong>same</strong> digit twice if it appears more than once in <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 31</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[3, 1]</code>.</li> <li>The possible products of any two digits are: <code>3 * 1 = 3</code>.</li> <li>The maximum product is 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 22</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[2, 2]</code>.</li> <li>The possible products of any two digits are: <code>2 * 2 = 4</code>.</li> <li>The maximum product is 4.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 124</span></p> <p><strong>Output:</strong> <span class="example-io">8</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[1, 2, 4]</code>.</li> <li>The possible products of any two digits are: <code>1 * 2 = 2</code>, <code>1 * 4 = 4</code>, <code>2 * 4 = 8</code>.</li> <li>The maximum product is 8.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>10 &lt;= n &lt;= 10<sup>9</sup></code></li> </ul>
Math; Sorting
Python
class Solution: def maxProduct(self, n: int) -> int: a = b = 0 while n: n, x = divmod(n, 10) if a < x: a, b = x, a elif b < x: b = x return a * b
3,536
Maximum Product of Two Digits
Easy
<p>You are given a positive integer <code>n</code>.</p> <p>Return the <strong>maximum</strong> product of any two digits in <code>n</code>.</p> <p><strong>Note:</strong> You may use the <strong>same</strong> digit twice if it appears more than once in <code>n</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 31</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[3, 1]</code>.</li> <li>The possible products of any two digits are: <code>3 * 1 = 3</code>.</li> <li>The maximum product is 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 22</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[2, 2]</code>.</li> <li>The possible products of any two digits are: <code>2 * 2 = 4</code>.</li> <li>The maximum product is 4.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 124</span></p> <p><strong>Output:</strong> <span class="example-io">8</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The digits of <code>n</code> are <code>[1, 2, 4]</code>.</li> <li>The possible products of any two digits are: <code>1 * 2 = 2</code>, <code>1 * 4 = 4</code>, <code>2 * 4 = 8</code>.</li> <li>The maximum product is 8.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>10 &lt;= n &lt;= 10<sup>9</sup></code></li> </ul>
Math; Sorting
TypeScript
function maxProduct(n: number): number { let [a, b] = [0, 0]; for (; n; n = Math.floor(n / 10)) { const x = n % 10; if (a < x) { [a, b] = [x, a]; } else if (b < x) { b = x; } } return a * b; }
3,541
Find Most Frequent Vowel and Consonant
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters (<code>&#39;a&#39;</code> to <code>&#39;z&#39;</code>). </p> <p>Your task is to:</p> <ul> <li>Find the vowel (one of <code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, or <code>&#39;u&#39;</code>) with the <strong>maximum</strong> frequency.</li> <li>Find the consonant (all other letters excluding vowels) with the <strong>maximum</strong> frequency.</li> </ul> <p>Return the sum of the two frequencies.</p> <p><strong>Note</strong>: If multiple vowels or consonants have the same maximum frequency, you may choose any one of them. If there are no vowels or no consonants in the string, consider their frequency as 0.</p> The <strong>frequency</strong> of a letter <code>x</code> is the number of times it occurs in the string. <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;successes&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;u&#39;</code> (frequency 1), <code>&#39;e&#39;</code> (frequency 2). The maximum frequency is 2.</li> <li>The consonants are: <code>&#39;s&#39;</code> (frequency 4), <code>&#39;c&#39;</code> (frequency 2). The maximum frequency is 4.</li> <li>The output is <code>2 + 4 = 6</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aeiaeia&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;a&#39;</code> (frequency 3), <code>&#39;e&#39;</code> ( frequency 2), <code>&#39;i&#39;</code> (frequency 2). The maximum frequency is 3.</li> <li>There are no consonants in <code>s</code>. Hence, maximum consonant frequency = 0.</li> <li>The output is <code>3 + 0 = 3</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 100</code></li> <li><code>s</code> consists of lowercase English letters only.</li> </ul>
Hash Table; String; Counting
C++
class Solution { public: int maxFreqSum(string s) { int cnt[26]{}; for (char c : s) { ++cnt[c - 'a']; } int a = 0, b = 0; for (int i = 0; i < 26; ++i) { char c = 'a' + i; if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u') { a = max(a, cnt[i]); } else { b = max(b, cnt[i]); } } return a + b; } };
3,541
Find Most Frequent Vowel and Consonant
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters (<code>&#39;a&#39;</code> to <code>&#39;z&#39;</code>). </p> <p>Your task is to:</p> <ul> <li>Find the vowel (one of <code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, or <code>&#39;u&#39;</code>) with the <strong>maximum</strong> frequency.</li> <li>Find the consonant (all other letters excluding vowels) with the <strong>maximum</strong> frequency.</li> </ul> <p>Return the sum of the two frequencies.</p> <p><strong>Note</strong>: If multiple vowels or consonants have the same maximum frequency, you may choose any one of them. If there are no vowels or no consonants in the string, consider their frequency as 0.</p> The <strong>frequency</strong> of a letter <code>x</code> is the number of times it occurs in the string. <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;successes&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;u&#39;</code> (frequency 1), <code>&#39;e&#39;</code> (frequency 2). The maximum frequency is 2.</li> <li>The consonants are: <code>&#39;s&#39;</code> (frequency 4), <code>&#39;c&#39;</code> (frequency 2). The maximum frequency is 4.</li> <li>The output is <code>2 + 4 = 6</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aeiaeia&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;a&#39;</code> (frequency 3), <code>&#39;e&#39;</code> ( frequency 2), <code>&#39;i&#39;</code> (frequency 2). The maximum frequency is 3.</li> <li>There are no consonants in <code>s</code>. Hence, maximum consonant frequency = 0.</li> <li>The output is <code>3 + 0 = 3</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 100</code></li> <li><code>s</code> consists of lowercase English letters only.</li> </ul>
Hash Table; String; Counting
Go
func maxFreqSum(s string) int { cnt := [26]int{} for _, c := range s { cnt[c-'a']++ } a, b := 0, 0 for i := range cnt { c := byte(i + 'a') if c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' { a = max(a, cnt[i]) } else { b = max(b, cnt[i]) } } return a + b }
3,541
Find Most Frequent Vowel and Consonant
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters (<code>&#39;a&#39;</code> to <code>&#39;z&#39;</code>). </p> <p>Your task is to:</p> <ul> <li>Find the vowel (one of <code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, or <code>&#39;u&#39;</code>) with the <strong>maximum</strong> frequency.</li> <li>Find the consonant (all other letters excluding vowels) with the <strong>maximum</strong> frequency.</li> </ul> <p>Return the sum of the two frequencies.</p> <p><strong>Note</strong>: If multiple vowels or consonants have the same maximum frequency, you may choose any one of them. If there are no vowels or no consonants in the string, consider their frequency as 0.</p> The <strong>frequency</strong> of a letter <code>x</code> is the number of times it occurs in the string. <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;successes&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;u&#39;</code> (frequency 1), <code>&#39;e&#39;</code> (frequency 2). The maximum frequency is 2.</li> <li>The consonants are: <code>&#39;s&#39;</code> (frequency 4), <code>&#39;c&#39;</code> (frequency 2). The maximum frequency is 4.</li> <li>The output is <code>2 + 4 = 6</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aeiaeia&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;a&#39;</code> (frequency 3), <code>&#39;e&#39;</code> ( frequency 2), <code>&#39;i&#39;</code> (frequency 2). The maximum frequency is 3.</li> <li>There are no consonants in <code>s</code>. Hence, maximum consonant frequency = 0.</li> <li>The output is <code>3 + 0 = 3</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 100</code></li> <li><code>s</code> consists of lowercase English letters only.</li> </ul>
Hash Table; String; Counting
Java
class Solution { public int maxFreqSum(String s) { int[] cnt = new int[26]; for (char c : s.toCharArray()) { ++cnt[c - 'a']; } int a = 0, b = 0; for (int i = 0; i < cnt.length; ++i) { char c = (char) (i + 'a'); if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u') { a = Math.max(a, cnt[i]); } else { b = Math.max(b, cnt[i]); } } return a + b; } }
3,541
Find Most Frequent Vowel and Consonant
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters (<code>&#39;a&#39;</code> to <code>&#39;z&#39;</code>). </p> <p>Your task is to:</p> <ul> <li>Find the vowel (one of <code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, or <code>&#39;u&#39;</code>) with the <strong>maximum</strong> frequency.</li> <li>Find the consonant (all other letters excluding vowels) with the <strong>maximum</strong> frequency.</li> </ul> <p>Return the sum of the two frequencies.</p> <p><strong>Note</strong>: If multiple vowels or consonants have the same maximum frequency, you may choose any one of them. If there are no vowels or no consonants in the string, consider their frequency as 0.</p> The <strong>frequency</strong> of a letter <code>x</code> is the number of times it occurs in the string. <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;successes&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;u&#39;</code> (frequency 1), <code>&#39;e&#39;</code> (frequency 2). The maximum frequency is 2.</li> <li>The consonants are: <code>&#39;s&#39;</code> (frequency 4), <code>&#39;c&#39;</code> (frequency 2). The maximum frequency is 4.</li> <li>The output is <code>2 + 4 = 6</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aeiaeia&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;a&#39;</code> (frequency 3), <code>&#39;e&#39;</code> ( frequency 2), <code>&#39;i&#39;</code> (frequency 2). The maximum frequency is 3.</li> <li>There are no consonants in <code>s</code>. Hence, maximum consonant frequency = 0.</li> <li>The output is <code>3 + 0 = 3</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 100</code></li> <li><code>s</code> consists of lowercase English letters only.</li> </ul>
Hash Table; String; Counting
Python
class Solution: def maxFreqSum(self, s: str) -> int: cnt = Counter(s) a = b = 0 for c, v in cnt.items(): if c in "aeiou": a = max(a, v) else: b = max(b, v) return a + b
3,541
Find Most Frequent Vowel and Consonant
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters (<code>&#39;a&#39;</code> to <code>&#39;z&#39;</code>). </p> <p>Your task is to:</p> <ul> <li>Find the vowel (one of <code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, or <code>&#39;u&#39;</code>) with the <strong>maximum</strong> frequency.</li> <li>Find the consonant (all other letters excluding vowels) with the <strong>maximum</strong> frequency.</li> </ul> <p>Return the sum of the two frequencies.</p> <p><strong>Note</strong>: If multiple vowels or consonants have the same maximum frequency, you may choose any one of them. If there are no vowels or no consonants in the string, consider their frequency as 0.</p> The <strong>frequency</strong> of a letter <code>x</code> is the number of times it occurs in the string. <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;successes&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;u&#39;</code> (frequency 1), <code>&#39;e&#39;</code> (frequency 2). The maximum frequency is 2.</li> <li>The consonants are: <code>&#39;s&#39;</code> (frequency 4), <code>&#39;c&#39;</code> (frequency 2). The maximum frequency is 4.</li> <li>The output is <code>2 + 4 = 6</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aeiaeia&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <ul> <li>The vowels are: <code>&#39;a&#39;</code> (frequency 3), <code>&#39;e&#39;</code> ( frequency 2), <code>&#39;i&#39;</code> (frequency 2). The maximum frequency is 3.</li> <li>There are no consonants in <code>s</code>. Hence, maximum consonant frequency = 0.</li> <li>The output is <code>3 + 0 = 3</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 100</code></li> <li><code>s</code> consists of lowercase English letters only.</li> </ul>
Hash Table; String; Counting
TypeScript
function maxFreqSum(s: string): number { const cnt: number[] = Array(26).fill(0); for (const c of s) { ++cnt[c.charCodeAt(0) - 97]; } let [a, b] = [0, 0]; for (let i = 0; i < 26; ++i) { const c = String.fromCharCode(i + 97); if ('aeiou'.includes(c)) { a = Math.max(a, cnt[i]); } else { b = Math.max(b, cnt[i]); } } return a + b; }
3,545
Minimum Deletions for At Most K Distinct Characters
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters, and an integer <code>k</code>.</p> <p>Your task is to delete some (possibly none) of the characters in the string so that the number of <strong>distinct</strong> characters in the resulting string is <strong>at most</strong> <code>k</code>.</p> <p>Return the <strong>minimum</strong> number of deletions required to achieve this.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has three distinct characters: <code>&#39;a&#39;</code>, <code>&#39;b&#39;</code> and <code>&#39;c&#39;</code>, each with a frequency of 1.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, remove all occurrences of any one character from the string.</li> <li>For example, removing all occurrences of <code>&#39;c&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aabb&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>) with frequencies of 2 and 2, respectively.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, no deletions are required. Thus, the answer is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;yyyzz&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;y&#39;</code> and <code>&#39;z&#39;</code>) with frequencies of 3 and 2, respectively.</li> <li>Since we can have at most <code>k = 1</code> distinct character, remove all occurrences of any one character from the string.</li> <li>Removing all <code>&#39;z&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 16</code></li> <li><code>1 &lt;= k &lt;= 16</code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul> <p> </p>
Greedy; Hash Table; String; Counting; Sorting
C++
class Solution { public: int minDeletion(string s, int k) { vector<int> cnt(26); for (char c : s) { ++cnt[c - 'a']; } ranges::sort(cnt); int ans = 0; for (int i = 0; i + k < 26; ++i) { ans += cnt[i]; } return ans; } };
3,545
Minimum Deletions for At Most K Distinct Characters
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters, and an integer <code>k</code>.</p> <p>Your task is to delete some (possibly none) of the characters in the string so that the number of <strong>distinct</strong> characters in the resulting string is <strong>at most</strong> <code>k</code>.</p> <p>Return the <strong>minimum</strong> number of deletions required to achieve this.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has three distinct characters: <code>&#39;a&#39;</code>, <code>&#39;b&#39;</code> and <code>&#39;c&#39;</code>, each with a frequency of 1.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, remove all occurrences of any one character from the string.</li> <li>For example, removing all occurrences of <code>&#39;c&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aabb&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>) with frequencies of 2 and 2, respectively.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, no deletions are required. Thus, the answer is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;yyyzz&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;y&#39;</code> and <code>&#39;z&#39;</code>) with frequencies of 3 and 2, respectively.</li> <li>Since we can have at most <code>k = 1</code> distinct character, remove all occurrences of any one character from the string.</li> <li>Removing all <code>&#39;z&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 16</code></li> <li><code>1 &lt;= k &lt;= 16</code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul> <p> </p>
Greedy; Hash Table; String; Counting; Sorting
Go
func minDeletion(s string, k int) (ans int) { cnt := make([]int, 26) for _, c := range s { cnt[c-'a']++ } sort.Ints(cnt) for i := 0; i+k < len(cnt); i++ { ans += cnt[i] } return }
3,545
Minimum Deletions for At Most K Distinct Characters
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters, and an integer <code>k</code>.</p> <p>Your task is to delete some (possibly none) of the characters in the string so that the number of <strong>distinct</strong> characters in the resulting string is <strong>at most</strong> <code>k</code>.</p> <p>Return the <strong>minimum</strong> number of deletions required to achieve this.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has three distinct characters: <code>&#39;a&#39;</code>, <code>&#39;b&#39;</code> and <code>&#39;c&#39;</code>, each with a frequency of 1.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, remove all occurrences of any one character from the string.</li> <li>For example, removing all occurrences of <code>&#39;c&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aabb&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>) with frequencies of 2 and 2, respectively.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, no deletions are required. Thus, the answer is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;yyyzz&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;y&#39;</code> and <code>&#39;z&#39;</code>) with frequencies of 3 and 2, respectively.</li> <li>Since we can have at most <code>k = 1</code> distinct character, remove all occurrences of any one character from the string.</li> <li>Removing all <code>&#39;z&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 16</code></li> <li><code>1 &lt;= k &lt;= 16</code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul> <p> </p>
Greedy; Hash Table; String; Counting; Sorting
Java
class Solution { public int minDeletion(String s, int k) { int[] cnt = new int[26]; for (char c : s.toCharArray()) { ++cnt[c - 'a']; } Arrays.sort(cnt); int ans = 0; for (int i = 0; i + k < 26; ++i) { ans += cnt[i]; } return ans; } }
3,545
Minimum Deletions for At Most K Distinct Characters
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters, and an integer <code>k</code>.</p> <p>Your task is to delete some (possibly none) of the characters in the string so that the number of <strong>distinct</strong> characters in the resulting string is <strong>at most</strong> <code>k</code>.</p> <p>Return the <strong>minimum</strong> number of deletions required to achieve this.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has three distinct characters: <code>&#39;a&#39;</code>, <code>&#39;b&#39;</code> and <code>&#39;c&#39;</code>, each with a frequency of 1.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, remove all occurrences of any one character from the string.</li> <li>For example, removing all occurrences of <code>&#39;c&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aabb&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>) with frequencies of 2 and 2, respectively.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, no deletions are required. Thus, the answer is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;yyyzz&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;y&#39;</code> and <code>&#39;z&#39;</code>) with frequencies of 3 and 2, respectively.</li> <li>Since we can have at most <code>k = 1</code> distinct character, remove all occurrences of any one character from the string.</li> <li>Removing all <code>&#39;z&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 16</code></li> <li><code>1 &lt;= k &lt;= 16</code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul> <p> </p>
Greedy; Hash Table; String; Counting; Sorting
Python
class Solution: def minDeletion(self, s: str, k: int) -> int: return sum(sorted(Counter(s).values())[:-k])
3,545
Minimum Deletions for At Most K Distinct Characters
Easy
<p>You are given a string <code>s</code> consisting of lowercase English letters, and an integer <code>k</code>.</p> <p>Your task is to delete some (possibly none) of the characters in the string so that the number of <strong>distinct</strong> characters in the resulting string is <strong>at most</strong> <code>k</code>.</p> <p>Return the <strong>minimum</strong> number of deletions required to achieve this.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has three distinct characters: <code>&#39;a&#39;</code>, <code>&#39;b&#39;</code> and <code>&#39;c&#39;</code>, each with a frequency of 1.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, remove all occurrences of any one character from the string.</li> <li>For example, removing all occurrences of <code>&#39;c&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;aabb&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>) with frequencies of 2 and 2, respectively.</li> <li>Since we can have at most <code>k = 2</code> distinct characters, no deletions are required. Thus, the answer is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;yyyzz&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>s</code> has two distinct characters (<code>&#39;y&#39;</code> and <code>&#39;z&#39;</code>) with frequencies of 3 and 2, respectively.</li> <li>Since we can have at most <code>k = 1</code> distinct character, remove all occurrences of any one character from the string.</li> <li>Removing all <code>&#39;z&#39;</code> results in at most <code>k</code> distinct characters. Thus, the answer is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 16</code></li> <li><code>1 &lt;= k &lt;= 16</code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul> <p> </p>
Greedy; Hash Table; String; Counting; Sorting
TypeScript
function minDeletion(s: string, k: number): number { const cnt: number[] = Array(26).fill(0); for (const c of s) { ++cnt[c.charCodeAt(0) - 97]; } cnt.sort((a, b) => a - b); return cnt.slice(0, 26 - k).reduce((a, b) => a + b, 0); }
3,546
Equal Sum Grid Partition I
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> of positive integers. Your task is to determine if it is possible to make <strong>either one horizontal or one vertical cut</strong> on the grid such that:</p> <ul> <li>Each of the two resulting sections formed by the cut is <strong>non-empty</strong>.</li> <li>The sum of the elements in both sections is <strong>equal</strong>.</li> </ul> <p>Return <code>true</code> if such a partition exists; otherwise return <code>false</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.png" style="width: 200px;" /><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.jpeg" style="width: 200px; height: 200px;" /></p> <p>A horizontal cut between row 0 and row 1 results in two non-empty sections, each with a sum of 5. Thus, the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,3],[2,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>No horizontal or vertical cut results in two non-empty sections with equal sums. Thus, the answer is <code>false</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == grid.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n == grid[i].length &lt;= 10<sup>5</sup></code></li> <li><code>2 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Enumeration; Matrix; Prefix Sum
C++
class Solution { public: bool canPartitionGrid(vector<vector<int>>& grid) { long long s = 0; for (const auto& row : grid) { for (int x : row) { s += x; } } if (s % 2 != 0) { return false; } int m = grid.size(), n = grid[0].size(); long long pre = 0; for (int i = 0; i < m; ++i) { for (int x : grid[i]) { pre += x; } if (pre * 2 == s && i + 1 < m) { return true; } } pre = 0; for (int j = 0; j < n; ++j) { for (int i = 0; i < m; ++i) { pre += grid[i][j]; } if (pre * 2 == s && j + 1 < n) { return true; } } return false; } };
3,546
Equal Sum Grid Partition I
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> of positive integers. Your task is to determine if it is possible to make <strong>either one horizontal or one vertical cut</strong> on the grid such that:</p> <ul> <li>Each of the two resulting sections formed by the cut is <strong>non-empty</strong>.</li> <li>The sum of the elements in both sections is <strong>equal</strong>.</li> </ul> <p>Return <code>true</code> if such a partition exists; otherwise return <code>false</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.png" style="width: 200px;" /><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.jpeg" style="width: 200px; height: 200px;" /></p> <p>A horizontal cut between row 0 and row 1 results in two non-empty sections, each with a sum of 5. Thus, the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,3],[2,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>No horizontal or vertical cut results in two non-empty sections with equal sums. Thus, the answer is <code>false</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == grid.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n == grid[i].length &lt;= 10<sup>5</sup></code></li> <li><code>2 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Enumeration; Matrix; Prefix Sum
Go
func canPartitionGrid(grid [][]int) bool { s := 0 for _, row := range grid { for _, x := range row { s += x } } if s%2 != 0 { return false } m, n := len(grid), len(grid[0]) pre := 0 for i, row := range grid { for _, x := range row { pre += x } if pre*2 == s && i+1 < m { return true } } pre = 0 for j := 0; j < n; j++ { for i := 0; i < m; i++ { pre += grid[i][j] } if pre*2 == s && j+1 < n { return true } } return false }
3,546
Equal Sum Grid Partition I
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> of positive integers. Your task is to determine if it is possible to make <strong>either one horizontal or one vertical cut</strong> on the grid such that:</p> <ul> <li>Each of the two resulting sections formed by the cut is <strong>non-empty</strong>.</li> <li>The sum of the elements in both sections is <strong>equal</strong>.</li> </ul> <p>Return <code>true</code> if such a partition exists; otherwise return <code>false</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.png" style="width: 200px;" /><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.jpeg" style="width: 200px; height: 200px;" /></p> <p>A horizontal cut between row 0 and row 1 results in two non-empty sections, each with a sum of 5. Thus, the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,3],[2,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>No horizontal or vertical cut results in two non-empty sections with equal sums. Thus, the answer is <code>false</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == grid.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n == grid[i].length &lt;= 10<sup>5</sup></code></li> <li><code>2 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Enumeration; Matrix; Prefix Sum
Java
class Solution { public boolean canPartitionGrid(int[][] grid) { long s = 0; for (var row : grid) { for (int x : row) { s += x; } } if (s % 2 != 0) { return false; } int m = grid.length, n = grid[0].length; long pre = 0; for (int i = 0; i < m; ++i) { for (int x : grid[i]) { pre += x; } if (pre * 2 == s && i < m - 1) { return true; } } pre = 0; for (int j = 0; j < n; ++j) { for (int i = 0; i < m; ++i) { pre += grid[i][j]; } if (pre * 2 == s && j < n - 1) { return true; } } return false; } }
3,546
Equal Sum Grid Partition I
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> of positive integers. Your task is to determine if it is possible to make <strong>either one horizontal or one vertical cut</strong> on the grid such that:</p> <ul> <li>Each of the two resulting sections formed by the cut is <strong>non-empty</strong>.</li> <li>The sum of the elements in both sections is <strong>equal</strong>.</li> </ul> <p>Return <code>true</code> if such a partition exists; otherwise return <code>false</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.png" style="width: 200px;" /><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.jpeg" style="width: 200px; height: 200px;" /></p> <p>A horizontal cut between row 0 and row 1 results in two non-empty sections, each with a sum of 5. Thus, the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,3],[2,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>No horizontal or vertical cut results in two non-empty sections with equal sums. Thus, the answer is <code>false</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == grid.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n == grid[i].length &lt;= 10<sup>5</sup></code></li> <li><code>2 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Enumeration; Matrix; Prefix Sum
Python
class Solution: def canPartitionGrid(self, grid: List[List[int]]) -> bool: s = sum(sum(row) for row in grid) if s % 2: return False pre = 0 for i, row in enumerate(grid): pre += sum(row) if pre * 2 == s and i != len(grid) - 1: return True pre = 0 for j, col in enumerate(zip(*grid)): pre += sum(col) if pre * 2 == s and j != len(grid[0]) - 1: return True return False
3,546
Equal Sum Grid Partition I
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> of positive integers. Your task is to determine if it is possible to make <strong>either one horizontal or one vertical cut</strong> on the grid such that:</p> <ul> <li>Each of the two resulting sections formed by the cut is <strong>non-empty</strong>.</li> <li>The sum of the elements in both sections is <strong>equal</strong>.</li> </ul> <p>Return <code>true</code> if such a partition exists; otherwise return <code>false</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.png" style="width: 200px;" /><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3546.Equal%20Sum%20Grid%20Partition%20I/images/lc.jpeg" style="width: 200px; height: 200px;" /></p> <p>A horizontal cut between row 0 and row 1 results in two non-empty sections, each with a sum of 5. Thus, the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,3],[2,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>No horizontal or vertical cut results in two non-empty sections with equal sums. Thus, the answer is <code>false</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == grid.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n == grid[i].length &lt;= 10<sup>5</sup></code></li> <li><code>2 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Enumeration; Matrix; Prefix Sum
TypeScript
function canPartitionGrid(grid: number[][]): boolean { let s = 0; for (const row of grid) { s += row.reduce((a, b) => a + b, 0); } if (s % 2 !== 0) { return false; } const [m, n] = [grid.length, grid[0].length]; let pre = 0; for (let i = 0; i < m; ++i) { pre += grid[i].reduce((a, b) => a + b, 0); if (pre * 2 === s && i + 1 < m) { return true; } } pre = 0; for (let j = 0; j < n; ++j) { for (let i = 0; i < m; ++i) { pre += grid[i][j]; } if (pre * 2 === s && j + 1 < n) { return true; } } return false; }
3,549
Multiply Two Polynomials
Hard
<p data-end="315" data-start="119">You are given two integer arrays <code>poly1</code> and <code>poly2</code>, where the element at index <code>i</code> in each array represents the coefficient of <code>x<sup>i</sup></code> in a polynomial.</p> <p>Let <code>A(x)</code> and <code>B(x)</code> be the polynomials represented by <code>poly1</code> and <code>poly2</code>, respectively.</p> <p>Return an integer array <code>result</code> of length <code>(poly1.length + poly2.length - 1)</code> representing the coefficients of the product polynomial <code>R(x) = A(x) * B(x)</code>, where <code>result[i]</code> denotes the coefficient of <code>x<sup>i</sup></code> in <code>R(x)</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [3,2,5], poly2 = [1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,14,13,20]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 3 + 2x + 5x<sup>2</sup></code> and <code>B(x) = 1 + 4x</code></li> <li><code>R(x) = (3 + 2x + 5x<sup>2</sup>) * (1 + 4x)</code></li> <li><code>R(x) = 3 * 1 + (3 * 4 + 2 * 1)x + (2 * 4 + 5 * 1)x<sup>2</sup> + (5 * 4)x<sup>3</sup></code></li> <li><code>R(x) = 3 + 14x + 13x<sup>2</sup> + 20x<sup>3</sup></code></li> <li>Thus, result = <code>[3, 14, 13, 20]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,0,-2], poly2 = [-1]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,0,2]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 0x - 2x<sup>2</sup></code> and <code>B(x) = -1</code></li> <li><code>R(x) = (1 + 0x - 2x<sup>2</sup>) * (-1)</code></li> <li><code>R(x) = -1 + 0x + 2x<sup>2</sup></code></li> <li>Thus, result = <code>[-1, 0, 2]</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,5,-3], poly2 = [-4,2,0]</span></p> <p><strong>Output:</strong> <span class="example-io">[-4,-18,22,-6,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 5x - 3x<sup>2</sup></code> and <code>B(x) = -4 + 2x + 0x<sup>2</sup></code></li> <li><code>R(x) = (1 + 5x - 3x<sup>2</sup>) * (-4 + 2x + 0x<sup>2</sup>)</code></li> <li><code>R(x) = 1 * -4 + (1 * 2 + 5 * -4)x + (5 * 2 + -3 * -4)x<sup>2</sup> + (-3 * 2)x<sup>3</sup> + 0x<sup>4</sup></code></li> <li><code>R(x) = -4 -18x + 22x<sup>2</sup> -6x<sup>3</sup> + 0x<sup>4</sup></code></li> <li>Thus, result = <code>[-4, -18, 22, -6, 0]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= poly1.length, poly2.length &lt;= 5 * 10<sup>4</sup></code></li> <li><code>-10<sup>3</sup> &lt;= poly1[i], poly2[i] &lt;= 10<sup>3</sup></code></li> <li><code>poly1</code> and <code>poly2</code> contain at least one non-zero coefficient.</li> </ul>
Array; Math
C++
class Solution { using cd = complex<double>; void fft(vector<cd>& a, bool invert) { int n = a.size(); for (int i = 1, j = 0; i < n; ++i) { int bit = n >> 1; for (; j & bit; bit >>= 1) j ^= bit; j ^= bit; if (i < j) swap(a[i], a[j]); } for (int len = 2; len <= n; len <<= 1) { double ang = 2 * M_PI / len * (invert ? -1 : 1); cd wlen(cos(ang), sin(ang)); for (int i = 0; i < n; i += len) { cd w(1, 0); int half = len >> 1; for (int j = 0; j < half; ++j) { cd u = a[i + j]; cd v = a[i + j + half] * w; a[i + j] = u + v; a[i + j + half] = u - v; w *= wlen; } } } if (invert) for (cd& x : a) x /= n; } public: vector<long long> multiply(vector<int>& poly1, vector<int>& poly2) { if (poly1.empty() || poly2.empty()) return {}; int m = poly1.size() + poly2.size() - 1; int n = 1; while (n < m) n <<= 1; vector<cd> fa(n), fb(n); for (int i = 0; i < n; ++i) { fa[i] = i < poly1.size() ? cd(poly1[i], 0) : cd(0, 0); fb[i] = i < poly2.size() ? cd(poly2[i], 0) : cd(0, 0); } fft(fa, false); fft(fb, false); for (int i = 0; i < n; ++i) fa[i] *= fb[i]; fft(fa, true); vector<long long> res(m); for (int i = 0; i < m; ++i) res[i] = llround(fa[i].real()); return res; } };
3,549
Multiply Two Polynomials
Hard
<p data-end="315" data-start="119">You are given two integer arrays <code>poly1</code> and <code>poly2</code>, where the element at index <code>i</code> in each array represents the coefficient of <code>x<sup>i</sup></code> in a polynomial.</p> <p>Let <code>A(x)</code> and <code>B(x)</code> be the polynomials represented by <code>poly1</code> and <code>poly2</code>, respectively.</p> <p>Return an integer array <code>result</code> of length <code>(poly1.length + poly2.length - 1)</code> representing the coefficients of the product polynomial <code>R(x) = A(x) * B(x)</code>, where <code>result[i]</code> denotes the coefficient of <code>x<sup>i</sup></code> in <code>R(x)</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [3,2,5], poly2 = [1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,14,13,20]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 3 + 2x + 5x<sup>2</sup></code> and <code>B(x) = 1 + 4x</code></li> <li><code>R(x) = (3 + 2x + 5x<sup>2</sup>) * (1 + 4x)</code></li> <li><code>R(x) = 3 * 1 + (3 * 4 + 2 * 1)x + (2 * 4 + 5 * 1)x<sup>2</sup> + (5 * 4)x<sup>3</sup></code></li> <li><code>R(x) = 3 + 14x + 13x<sup>2</sup> + 20x<sup>3</sup></code></li> <li>Thus, result = <code>[3, 14, 13, 20]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,0,-2], poly2 = [-1]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,0,2]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 0x - 2x<sup>2</sup></code> and <code>B(x) = -1</code></li> <li><code>R(x) = (1 + 0x - 2x<sup>2</sup>) * (-1)</code></li> <li><code>R(x) = -1 + 0x + 2x<sup>2</sup></code></li> <li>Thus, result = <code>[-1, 0, 2]</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,5,-3], poly2 = [-4,2,0]</span></p> <p><strong>Output:</strong> <span class="example-io">[-4,-18,22,-6,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 5x - 3x<sup>2</sup></code> and <code>B(x) = -4 + 2x + 0x<sup>2</sup></code></li> <li><code>R(x) = (1 + 5x - 3x<sup>2</sup>) * (-4 + 2x + 0x<sup>2</sup>)</code></li> <li><code>R(x) = 1 * -4 + (1 * 2 + 5 * -4)x + (5 * 2 + -3 * -4)x<sup>2</sup> + (-3 * 2)x<sup>3</sup> + 0x<sup>4</sup></code></li> <li><code>R(x) = -4 -18x + 22x<sup>2</sup> -6x<sup>3</sup> + 0x<sup>4</sup></code></li> <li>Thus, result = <code>[-4, -18, 22, -6, 0]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= poly1.length, poly2.length &lt;= 5 * 10<sup>4</sup></code></li> <li><code>-10<sup>3</sup> &lt;= poly1[i], poly2[i] &lt;= 10<sup>3</sup></code></li> <li><code>poly1</code> and <code>poly2</code> contain at least one non-zero coefficient.</li> </ul>
Array; Math
Go
func multiply(poly1 []int, poly2 []int) []int64 { if len(poly1) == 0 || len(poly2) == 0 { return []int64{} } m := len(poly1) + len(poly2) - 1 n := 1 for n < m { n <<= 1 } fa := make([]complex128, n) fb := make([]complex128, n) for i := 0; i < len(poly1); i++ { fa[i] = complex(float64(poly1[i]), 0) } for i := 0; i < len(poly2); i++ { fb[i] = complex(float64(poly2[i]), 0) } fft(fa, false) fft(fb, false) for i := 0; i < n; i++ { fa[i] *= fb[i] } fft(fa, true) res := make([]int64, m) for i := 0; i < m; i++ { res[i] = int64(math.Round(real(fa[i]))) } return res } func fft(a []complex128, invert bool) { n := len(a) for i, j := 1, 0; i < n; i++ { bit := n >> 1 for ; j&bit != 0; bit >>= 1 { j ^= bit } j ^= bit if i < j { a[i], a[j] = a[j], a[i] } } for length := 2; length <= n; length <<= 1 { angle := 2 * math.Pi / float64(length) if invert { angle = -angle } wlen := cmplx.Rect(1, angle) for i := 0; i < n; i += length { w := complex(1, 0) half := length >> 1 for j := 0; j < half; j++ { u := a[i+j] v := a[i+j+half] * w a[i+j] = u + v a[i+j+half] = u - v w *= wlen } } } if invert { for i := range a { a[i] /= complex(float64(n), 0) } } }
3,549
Multiply Two Polynomials
Hard
<p data-end="315" data-start="119">You are given two integer arrays <code>poly1</code> and <code>poly2</code>, where the element at index <code>i</code> in each array represents the coefficient of <code>x<sup>i</sup></code> in a polynomial.</p> <p>Let <code>A(x)</code> and <code>B(x)</code> be the polynomials represented by <code>poly1</code> and <code>poly2</code>, respectively.</p> <p>Return an integer array <code>result</code> of length <code>(poly1.length + poly2.length - 1)</code> representing the coefficients of the product polynomial <code>R(x) = A(x) * B(x)</code>, where <code>result[i]</code> denotes the coefficient of <code>x<sup>i</sup></code> in <code>R(x)</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [3,2,5], poly2 = [1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,14,13,20]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 3 + 2x + 5x<sup>2</sup></code> and <code>B(x) = 1 + 4x</code></li> <li><code>R(x) = (3 + 2x + 5x<sup>2</sup>) * (1 + 4x)</code></li> <li><code>R(x) = 3 * 1 + (3 * 4 + 2 * 1)x + (2 * 4 + 5 * 1)x<sup>2</sup> + (5 * 4)x<sup>3</sup></code></li> <li><code>R(x) = 3 + 14x + 13x<sup>2</sup> + 20x<sup>3</sup></code></li> <li>Thus, result = <code>[3, 14, 13, 20]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,0,-2], poly2 = [-1]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,0,2]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 0x - 2x<sup>2</sup></code> and <code>B(x) = -1</code></li> <li><code>R(x) = (1 + 0x - 2x<sup>2</sup>) * (-1)</code></li> <li><code>R(x) = -1 + 0x + 2x<sup>2</sup></code></li> <li>Thus, result = <code>[-1, 0, 2]</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,5,-3], poly2 = [-4,2,0]</span></p> <p><strong>Output:</strong> <span class="example-io">[-4,-18,22,-6,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 5x - 3x<sup>2</sup></code> and <code>B(x) = -4 + 2x + 0x<sup>2</sup></code></li> <li><code>R(x) = (1 + 5x - 3x<sup>2</sup>) * (-4 + 2x + 0x<sup>2</sup>)</code></li> <li><code>R(x) = 1 * -4 + (1 * 2 + 5 * -4)x + (5 * 2 + -3 * -4)x<sup>2</sup> + (-3 * 2)x<sup>3</sup> + 0x<sup>4</sup></code></li> <li><code>R(x) = -4 -18x + 22x<sup>2</sup> -6x<sup>3</sup> + 0x<sup>4</sup></code></li> <li>Thus, result = <code>[-4, -18, 22, -6, 0]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= poly1.length, poly2.length &lt;= 5 * 10<sup>4</sup></code></li> <li><code>-10<sup>3</sup> &lt;= poly1[i], poly2[i] &lt;= 10<sup>3</sup></code></li> <li><code>poly1</code> and <code>poly2</code> contain at least one non-zero coefficient.</li> </ul>
Array; Math
Java
class Solution { public long[] multiply(int[] poly1, int[] poly2) { if (poly1 == null || poly2 == null || poly1.length == 0 || poly2.length == 0) { return new long[0]; } int m = poly1.length + poly2.length - 1; int n = 1; while (n < m) n <<= 1; Complex[] fa = new Complex[n]; Complex[] fb = new Complex[n]; for (int i = 0; i < n; i++) { fa[i] = new Complex(i < poly1.length ? poly1[i] : 0, 0); fb[i] = new Complex(i < poly2.length ? poly2[i] : 0, 0); } fft(fa, false); fft(fb, false); for (int i = 0; i < n; i++) { fa[i] = fa[i].mul(fb[i]); } fft(fa, true); long[] res = new long[m]; for (int i = 0; i < m; i++) { res[i] = Math.round(fa[i].re); } return res; } private static void fft(Complex[] a, boolean invert) { int n = a.length; for (int i = 1, j = 0; i < n; i++) { int bit = n >>> 1; while ((j & bit) != 0) { j ^= bit; bit >>>= 1; } j ^= bit; if (i < j) { Complex tmp = a[i]; a[i] = a[j]; a[j] = tmp; } } for (int len = 2; len <= n; len <<= 1) { double ang = 2 * Math.PI / len * (invert ? -1 : 1); Complex wlen = new Complex(Math.cos(ang), Math.sin(ang)); for (int i = 0; i < n; i += len) { Complex w = new Complex(1, 0); int half = len >>> 1; for (int j = 0; j < half; j++) { Complex u = a[i + j]; Complex v = a[i + j + half].mul(w); a[i + j] = u.add(v); a[i + j + half] = u.sub(v); w = w.mul(wlen); } } } if (invert) { for (int i = 0; i < n; i++) { a[i].re /= n; a[i].im /= n; } } } private static final class Complex { double re, im; Complex(double re, double im) { this.re = re; this.im = im; } Complex add(Complex o) { return new Complex(re + o.re, im + o.im); } Complex sub(Complex o) { return new Complex(re - o.re, im - o.im); } Complex mul(Complex o) { return new Complex(re * o.re - im * o.im, re * o.im + im * o.re); } } }
3,549
Multiply Two Polynomials
Hard
<p data-end="315" data-start="119">You are given two integer arrays <code>poly1</code> and <code>poly2</code>, where the element at index <code>i</code> in each array represents the coefficient of <code>x<sup>i</sup></code> in a polynomial.</p> <p>Let <code>A(x)</code> and <code>B(x)</code> be the polynomials represented by <code>poly1</code> and <code>poly2</code>, respectively.</p> <p>Return an integer array <code>result</code> of length <code>(poly1.length + poly2.length - 1)</code> representing the coefficients of the product polynomial <code>R(x) = A(x) * B(x)</code>, where <code>result[i]</code> denotes the coefficient of <code>x<sup>i</sup></code> in <code>R(x)</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [3,2,5], poly2 = [1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,14,13,20]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 3 + 2x + 5x<sup>2</sup></code> and <code>B(x) = 1 + 4x</code></li> <li><code>R(x) = (3 + 2x + 5x<sup>2</sup>) * (1 + 4x)</code></li> <li><code>R(x) = 3 * 1 + (3 * 4 + 2 * 1)x + (2 * 4 + 5 * 1)x<sup>2</sup> + (5 * 4)x<sup>3</sup></code></li> <li><code>R(x) = 3 + 14x + 13x<sup>2</sup> + 20x<sup>3</sup></code></li> <li>Thus, result = <code>[3, 14, 13, 20]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,0,-2], poly2 = [-1]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,0,2]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 0x - 2x<sup>2</sup></code> and <code>B(x) = -1</code></li> <li><code>R(x) = (1 + 0x - 2x<sup>2</sup>) * (-1)</code></li> <li><code>R(x) = -1 + 0x + 2x<sup>2</sup></code></li> <li>Thus, result = <code>[-1, 0, 2]</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,5,-3], poly2 = [-4,2,0]</span></p> <p><strong>Output:</strong> <span class="example-io">[-4,-18,22,-6,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 5x - 3x<sup>2</sup></code> and <code>B(x) = -4 + 2x + 0x<sup>2</sup></code></li> <li><code>R(x) = (1 + 5x - 3x<sup>2</sup>) * (-4 + 2x + 0x<sup>2</sup>)</code></li> <li><code>R(x) = 1 * -4 + (1 * 2 + 5 * -4)x + (5 * 2 + -3 * -4)x<sup>2</sup> + (-3 * 2)x<sup>3</sup> + 0x<sup>4</sup></code></li> <li><code>R(x) = -4 -18x + 22x<sup>2</sup> -6x<sup>3</sup> + 0x<sup>4</sup></code></li> <li>Thus, result = <code>[-4, -18, 22, -6, 0]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= poly1.length, poly2.length &lt;= 5 * 10<sup>4</sup></code></li> <li><code>-10<sup>3</sup> &lt;= poly1[i], poly2[i] &lt;= 10<sup>3</sup></code></li> <li><code>poly1</code> and <code>poly2</code> contain at least one non-zero coefficient.</li> </ul>
Array; Math
Python
class Solution: def multiply(self, poly1: List[int], poly2: List[int]) -> List[int]: if not poly1 or not poly2: return [] m = len(poly1) + len(poly2) - 1 n = 1 while n < m: n <<= 1 fa = list(map(complex, poly1)) + [0j] * (n - len(poly1)) fb = list(map(complex, poly2)) + [0j] * (n - len(poly2)) self._fft(fa, invert=False) self._fft(fb, invert=False) for i in range(n): fa[i] *= fb[i] self._fft(fa, invert=True) return [int(round(fa[i].real)) for i in range(m)] def _fft(self, a: List[complex], invert: bool) -> None: n = len(a) j = 0 for i in range(1, n): bit = n >> 1 while j & bit: j ^= bit bit >>= 1 j ^= bit if i < j: a[i], a[j] = a[j], a[i] len_ = 2 while len_ <= n: ang = 2 * math.pi / len_ * (-1 if invert else 1) wlen = complex(math.cos(ang), math.sin(ang)) for i in range(0, n, len_): w = 1 + 0j half = i + len_ // 2 for j in range(i, half): u = a[j] v = a[j + len_ // 2] * w a[j] = u + v a[j + len_ // 2] = u - v w *= wlen len_ <<= 1 if invert: for i in range(n): a[i] /= n
3,549
Multiply Two Polynomials
Hard
<p data-end="315" data-start="119">You are given two integer arrays <code>poly1</code> and <code>poly2</code>, where the element at index <code>i</code> in each array represents the coefficient of <code>x<sup>i</sup></code> in a polynomial.</p> <p>Let <code>A(x)</code> and <code>B(x)</code> be the polynomials represented by <code>poly1</code> and <code>poly2</code>, respectively.</p> <p>Return an integer array <code>result</code> of length <code>(poly1.length + poly2.length - 1)</code> representing the coefficients of the product polynomial <code>R(x) = A(x) * B(x)</code>, where <code>result[i]</code> denotes the coefficient of <code>x<sup>i</sup></code> in <code>R(x)</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [3,2,5], poly2 = [1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,14,13,20]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 3 + 2x + 5x<sup>2</sup></code> and <code>B(x) = 1 + 4x</code></li> <li><code>R(x) = (3 + 2x + 5x<sup>2</sup>) * (1 + 4x)</code></li> <li><code>R(x) = 3 * 1 + (3 * 4 + 2 * 1)x + (2 * 4 + 5 * 1)x<sup>2</sup> + (5 * 4)x<sup>3</sup></code></li> <li><code>R(x) = 3 + 14x + 13x<sup>2</sup> + 20x<sup>3</sup></code></li> <li>Thus, result = <code>[3, 14, 13, 20]</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,0,-2], poly2 = [-1]</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,0,2]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 0x - 2x<sup>2</sup></code> and <code>B(x) = -1</code></li> <li><code>R(x) = (1 + 0x - 2x<sup>2</sup>) * (-1)</code></li> <li><code>R(x) = -1 + 0x + 2x<sup>2</sup></code></li> <li>Thus, result = <code>[-1, 0, 2]</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">poly1 = [1,5,-3], poly2 = [-4,2,0]</span></p> <p><strong>Output:</strong> <span class="example-io">[-4,-18,22,-6,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>A(x) = 1 + 5x - 3x<sup>2</sup></code> and <code>B(x) = -4 + 2x + 0x<sup>2</sup></code></li> <li><code>R(x) = (1 + 5x - 3x<sup>2</sup>) * (-4 + 2x + 0x<sup>2</sup>)</code></li> <li><code>R(x) = 1 * -4 + (1 * 2 + 5 * -4)x + (5 * 2 + -3 * -4)x<sup>2</sup> + (-3 * 2)x<sup>3</sup> + 0x<sup>4</sup></code></li> <li><code>R(x) = -4 -18x + 22x<sup>2</sup> -6x<sup>3</sup> + 0x<sup>4</sup></code></li> <li>Thus, result = <code>[-4, -18, 22, -6, 0]</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= poly1.length, poly2.length &lt;= 5 * 10<sup>4</sup></code></li> <li><code>-10<sup>3</sup> &lt;= poly1[i], poly2[i] &lt;= 10<sup>3</sup></code></li> <li><code>poly1</code> and <code>poly2</code> contain at least one non-zero coefficient.</li> </ul>
Array; Math
TypeScript
export function multiply(poly1: number[], poly2: number[]): number[] { const n1 = poly1.length, n2 = poly2.length; if (!n1 || !n2) return []; if (Math.min(n1, n2) <= 64) { const m = n1 + n2 - 1, res = new Array<number>(m).fill(0); for (let i = 0; i < n1; ++i) for (let j = 0; j < n2; ++j) res[i + j] += poly1[i] * poly2[j]; return res.map(v => Math.round(v)); } let n = 1, m = n1 + n2 - 1; while (n < m) n <<= 1; const reA = new Float64Array(n); const imA = new Float64Array(n); for (let i = 0; i < n1; ++i) reA[i] = poly1[i]; const reB = new Float64Array(n); const imB = new Float64Array(n); for (let i = 0; i < n2; ++i) reB[i] = poly2[i]; fft(reA, imA, false); fft(reB, imB, false); for (let i = 0; i < n; ++i) { const a = reA[i], b = imA[i], c = reB[i], d = imB[i]; reA[i] = a * c - b * d; imA[i] = a * d + b * c; } fft(reA, imA, true); const out = new Array<number>(m); for (let i = 0; i < m; ++i) out[i] = Math.round(reA[i]); return out; } function fft(re: Float64Array, im: Float64Array, invert: boolean): void { const n = re.length; for (let i = 1, j = 0; i < n; ++i) { let bit = n >> 1; for (; j & bit; bit >>= 1) j ^= bit; j ^= bit; if (i < j) { [re[i], re[j]] = [re[j], re[i]]; [im[i], im[j]] = [im[j], im[i]]; } } for (let len = 2; len <= n; len <<= 1) { const ang = ((2 * Math.PI) / len) * (invert ? -1 : 1); const wlenCos = Math.cos(ang), wlenSin = Math.sin(ang); for (let i = 0; i < n; i += len) { let wRe = 1, wIm = 0; const half = len >> 1; for (let j = 0; j < half; ++j) { const uRe = re[i + j], uIm = im[i + j]; const vRe0 = re[i + j + half], vIm0 = im[i + j + half]; const vRe = vRe0 * wRe - vIm0 * wIm; const vIm = vRe0 * wIm + vIm0 * wRe; re[i + j] = uRe + vRe; im[i + j] = uIm + vIm; re[i + j + half] = uRe - vRe; im[i + j + half] = uIm - vIm; const nextWRe = wRe * wlenCos - wIm * wlenSin; wIm = wRe * wlenSin + wIm * wlenCos; wRe = nextWRe; } } } if (invert) { for (let i = 0; i < n; ++i) { re[i] /= n; im[i] /= n; } } }
3,550
Smallest Index With Digit Sum Equal to Index
Easy
<p>You are given an integer array <code>nums</code>.</p> <p>Return the <strong>smallest</strong> index <code>i</code> such that the sum of the digits of <code>nums[i]</code> is equal to <code>i</code>.</p> <p>If no such index exists, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[2] = 2</code>, the sum of digits is 2, which is equal to index <code>i = 2</code>. Thus, the output is 2.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,11]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[1] = 10</code>, the sum of digits is <code>1 + 0 = 1</code>, which is equal to index <code>i = 1</code>.</li> <li>For <code>nums[2] = 11</code>, the sum of digits is <code>1 + 1 = 2</code>, which is equal to index <code>i = 2</code>.</li> <li>Since index 1 is the smallest, the output is 1.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Since no index satisfies the condition, the output is -1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math
C++
class Solution { public: int smallestIndex(vector<int>& nums) { for (int i = 0; i < nums.size(); ++i) { int s = 0; while (nums[i]) { s += nums[i] % 10; nums[i] /= 10; } if (s == i) { return i; } } return -1; } };
3,550
Smallest Index With Digit Sum Equal to Index
Easy
<p>You are given an integer array <code>nums</code>.</p> <p>Return the <strong>smallest</strong> index <code>i</code> such that the sum of the digits of <code>nums[i]</code> is equal to <code>i</code>.</p> <p>If no such index exists, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[2] = 2</code>, the sum of digits is 2, which is equal to index <code>i = 2</code>. Thus, the output is 2.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,11]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[1] = 10</code>, the sum of digits is <code>1 + 0 = 1</code>, which is equal to index <code>i = 1</code>.</li> <li>For <code>nums[2] = 11</code>, the sum of digits is <code>1 + 1 = 2</code>, which is equal to index <code>i = 2</code>.</li> <li>Since index 1 is the smallest, the output is 1.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Since no index satisfies the condition, the output is -1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math
Go
func smallestIndex(nums []int) int { for i, x := range nums { s := 0 for ; x > 0; x /= 10 { s += x % 10 } if s == i { return i } } return -1 }
3,550
Smallest Index With Digit Sum Equal to Index
Easy
<p>You are given an integer array <code>nums</code>.</p> <p>Return the <strong>smallest</strong> index <code>i</code> such that the sum of the digits of <code>nums[i]</code> is equal to <code>i</code>.</p> <p>If no such index exists, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[2] = 2</code>, the sum of digits is 2, which is equal to index <code>i = 2</code>. Thus, the output is 2.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,11]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[1] = 10</code>, the sum of digits is <code>1 + 0 = 1</code>, which is equal to index <code>i = 1</code>.</li> <li>For <code>nums[2] = 11</code>, the sum of digits is <code>1 + 1 = 2</code>, which is equal to index <code>i = 2</code>.</li> <li>Since index 1 is the smallest, the output is 1.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Since no index satisfies the condition, the output is -1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math
Java
class Solution { public int smallestIndex(int[] nums) { for (int i = 0; i < nums.length; ++i) { int s = 0; while (nums[i] != 0) { s += nums[i] % 10; nums[i] /= 10; } if (s == i) { return i; } } return -1; } }
3,550
Smallest Index With Digit Sum Equal to Index
Easy
<p>You are given an integer array <code>nums</code>.</p> <p>Return the <strong>smallest</strong> index <code>i</code> such that the sum of the digits of <code>nums[i]</code> is equal to <code>i</code>.</p> <p>If no such index exists, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[2] = 2</code>, the sum of digits is 2, which is equal to index <code>i = 2</code>. Thus, the output is 2.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,11]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[1] = 10</code>, the sum of digits is <code>1 + 0 = 1</code>, which is equal to index <code>i = 1</code>.</li> <li>For <code>nums[2] = 11</code>, the sum of digits is <code>1 + 1 = 2</code>, which is equal to index <code>i = 2</code>.</li> <li>Since index 1 is the smallest, the output is 1.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Since no index satisfies the condition, the output is -1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math
Python
class Solution: def smallestIndex(self, nums: List[int]) -> int: for i, x in enumerate(nums): s = 0 while x: s += x % 10 x //= 10 if s == i: return i return -1
3,550
Smallest Index With Digit Sum Equal to Index
Easy
<p>You are given an integer array <code>nums</code>.</p> <p>Return the <strong>smallest</strong> index <code>i</code> such that the sum of the digits of <code>nums[i]</code> is equal to <code>i</code>.</p> <p>If no such index exists, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[2] = 2</code>, the sum of digits is 2, which is equal to index <code>i = 2</code>. Thus, the output is 2.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,11]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>For <code>nums[1] = 10</code>, the sum of digits is <code>1 + 0 = 1</code>, which is equal to index <code>i = 1</code>.</li> <li>For <code>nums[2] = 11</code>, the sum of digits is <code>1 + 1 = 2</code>, which is equal to index <code>i = 2</code>.</li> <li>Since index 1 is the smallest, the output is 1.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Since no index satisfies the condition, the output is -1.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>0 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math
TypeScript
function smallestIndex(nums: number[]): number { for (let i = 0; i < nums.length; ++i) { let s = 0; for (; nums[i] > 0; nums[i] = Math.floor(nums[i] / 10)) { s += nums[i] % 10; } if (s === i) { return i; } } return -1; }
3,551
Minimum Swaps to Sort by Digit Sum
Medium
<p>You are given an array <code>nums</code> of <strong>distinct</strong> positive integers. You need to sort the array in <strong>increasing</strong> order based on the sum of the digits of each number. If two numbers have the same digit sum, the <strong>smaller</strong> number appears first in the sorted order.</p> <p>Return the <strong>minimum</strong> number of swaps required to rearrange <code>nums</code> into this sorted order.</p> <p>A <strong>swap</strong> is defined as exchanging the values at two distinct positions in the array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [37,100]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[3 + 7 = 10, 1 + 0 + 0 = 1] &rarr; [10, 1]</code></li> <li>Sort the integers based on digit sum: <code>[100, 37]</code>. Swap <code>37</code> with <code>100</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [22,14,33,7]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[2 + 2 = 4, 1 + 4 = 5, 3 + 3 = 6, 7 = 7] &rarr; [4, 5, 6, 7]</code></li> <li>Sort the integers based on digit sum: <code>[22, 14, 33, 7]</code>. The array is already sorted.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [18,43,34,16]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[1 + 8 = 9, 4 + 3 = 7, 3 + 4 = 7, 1 + 6 = 7] &rarr; [9, 7, 7, 7]</code></li> <li>Sort the integers based on digit sum: <code>[16, 34, 43, 18]</code>. Swap <code>18</code> with <code>16</code>, and swap <code>43</code> with <code>34</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>nums</code> consists of <strong>distinct</strong> positive integers.</li> </ul>
Array; Hash Table; Sorting
C++
class Solution { public: int f(int x) { int s = 0; while (x) { s += x % 10; x /= 10; } return s; } int minSwaps(vector<int>& nums) { int n = nums.size(); vector<pair<int, int>> arr(n); for (int i = 0; i < n; ++i) arr[i] = {f(nums[i]), nums[i]}; sort(arr.begin(), arr.end()); unordered_map<int, int> d; for (int i = 0; i < n; ++i) d[arr[i].second] = i; vector<char> vis(n, 0); int ans = n; for (int i = 0; i < n; ++i) { if (!vis[i]) { --ans; int j = i; while (!vis[j]) { vis[j] = 1; j = d[nums[j]]; } } } return ans; } };
3,551
Minimum Swaps to Sort by Digit Sum
Medium
<p>You are given an array <code>nums</code> of <strong>distinct</strong> positive integers. You need to sort the array in <strong>increasing</strong> order based on the sum of the digits of each number. If two numbers have the same digit sum, the <strong>smaller</strong> number appears first in the sorted order.</p> <p>Return the <strong>minimum</strong> number of swaps required to rearrange <code>nums</code> into this sorted order.</p> <p>A <strong>swap</strong> is defined as exchanging the values at two distinct positions in the array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [37,100]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[3 + 7 = 10, 1 + 0 + 0 = 1] &rarr; [10, 1]</code></li> <li>Sort the integers based on digit sum: <code>[100, 37]</code>. Swap <code>37</code> with <code>100</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [22,14,33,7]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[2 + 2 = 4, 1 + 4 = 5, 3 + 3 = 6, 7 = 7] &rarr; [4, 5, 6, 7]</code></li> <li>Sort the integers based on digit sum: <code>[22, 14, 33, 7]</code>. The array is already sorted.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [18,43,34,16]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[1 + 8 = 9, 4 + 3 = 7, 3 + 4 = 7, 1 + 6 = 7] &rarr; [9, 7, 7, 7]</code></li> <li>Sort the integers based on digit sum: <code>[16, 34, 43, 18]</code>. Swap <code>18</code> with <code>16</code>, and swap <code>43</code> with <code>34</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>nums</code> consists of <strong>distinct</strong> positive integers.</li> </ul>
Array; Hash Table; Sorting
Go
func minSwaps(nums []int) int { n := len(nums) arr := make([][2]int, n) for i := 0; i < n; i++ { arr[i][0] = f(nums[i]) arr[i][1] = nums[i] } sort.Slice(arr, func(i, j int) bool { if arr[i][0] != arr[j][0] { return arr[i][0] < arr[j][0] } return arr[i][1] < arr[j][1] }) d := make(map[int]int, n) for i := 0; i < n; i++ { d[arr[i][1]] = i } vis := make([]bool, n) ans := n for i := 0; i < n; i++ { if !vis[i] { ans-- j := i for !vis[j] { vis[j] = true j = d[nums[j]] } } } return ans } func f(x int) int { s := 0 for x != 0 { s += x % 10 x /= 10 } return s }
3,551
Minimum Swaps to Sort by Digit Sum
Medium
<p>You are given an array <code>nums</code> of <strong>distinct</strong> positive integers. You need to sort the array in <strong>increasing</strong> order based on the sum of the digits of each number. If two numbers have the same digit sum, the <strong>smaller</strong> number appears first in the sorted order.</p> <p>Return the <strong>minimum</strong> number of swaps required to rearrange <code>nums</code> into this sorted order.</p> <p>A <strong>swap</strong> is defined as exchanging the values at two distinct positions in the array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [37,100]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[3 + 7 = 10, 1 + 0 + 0 = 1] &rarr; [10, 1]</code></li> <li>Sort the integers based on digit sum: <code>[100, 37]</code>. Swap <code>37</code> with <code>100</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [22,14,33,7]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[2 + 2 = 4, 1 + 4 = 5, 3 + 3 = 6, 7 = 7] &rarr; [4, 5, 6, 7]</code></li> <li>Sort the integers based on digit sum: <code>[22, 14, 33, 7]</code>. The array is already sorted.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [18,43,34,16]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[1 + 8 = 9, 4 + 3 = 7, 3 + 4 = 7, 1 + 6 = 7] &rarr; [9, 7, 7, 7]</code></li> <li>Sort the integers based on digit sum: <code>[16, 34, 43, 18]</code>. Swap <code>18</code> with <code>16</code>, and swap <code>43</code> with <code>34</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>nums</code> consists of <strong>distinct</strong> positive integers.</li> </ul>
Array; Hash Table; Sorting
Java
class Solution { public int minSwaps(int[] nums) { int n = nums.length; int[][] arr = new int[n][2]; for (int i = 0; i < n; i++) { arr[i][0] = f(nums[i]); arr[i][1] = nums[i]; } Arrays.sort(arr, (a, b) -> { if (a[0] != b[0]) return Integer.compare(a[0], b[0]); return Integer.compare(a[1], b[1]); }); Map<Integer, Integer> d = new HashMap<>(); for (int i = 0; i < n; i++) { d.put(arr[i][1], i); } boolean[] vis = new boolean[n]; int ans = n; for (int i = 0; i < n; i++) { if (!vis[i]) { ans--; int j = i; while (!vis[j]) { vis[j] = true; j = d.get(nums[j]); } } } return ans; } private int f(int x) { int s = 0; while (x != 0) { s += x % 10; x /= 10; } return s; } }
3,551
Minimum Swaps to Sort by Digit Sum
Medium
<p>You are given an array <code>nums</code> of <strong>distinct</strong> positive integers. You need to sort the array in <strong>increasing</strong> order based on the sum of the digits of each number. If two numbers have the same digit sum, the <strong>smaller</strong> number appears first in the sorted order.</p> <p>Return the <strong>minimum</strong> number of swaps required to rearrange <code>nums</code> into this sorted order.</p> <p>A <strong>swap</strong> is defined as exchanging the values at two distinct positions in the array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [37,100]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[3 + 7 = 10, 1 + 0 + 0 = 1] &rarr; [10, 1]</code></li> <li>Sort the integers based on digit sum: <code>[100, 37]</code>. Swap <code>37</code> with <code>100</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [22,14,33,7]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[2 + 2 = 4, 1 + 4 = 5, 3 + 3 = 6, 7 = 7] &rarr; [4, 5, 6, 7]</code></li> <li>Sort the integers based on digit sum: <code>[22, 14, 33, 7]</code>. The array is already sorted.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [18,43,34,16]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[1 + 8 = 9, 4 + 3 = 7, 3 + 4 = 7, 1 + 6 = 7] &rarr; [9, 7, 7, 7]</code></li> <li>Sort the integers based on digit sum: <code>[16, 34, 43, 18]</code>. Swap <code>18</code> with <code>16</code>, and swap <code>43</code> with <code>34</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>nums</code> consists of <strong>distinct</strong> positive integers.</li> </ul>
Array; Hash Table; Sorting
Python
class Solution: def minSwaps(self, nums: List[int]) -> int: def f(x: int) -> int: s = 0 while x: s += x % 10 x //= 10 return s n = len(nums) arr = sorted((f(x), x) for x in nums) d = {a[1]: i for i, a in enumerate(arr)} ans = n vis = [False] * n for i in range(n): if not vis[i]: ans -= 1 j = i while not vis[j]: vis[j] = True j = d[nums[j]] return ans
3,551
Minimum Swaps to Sort by Digit Sum
Medium
<p>You are given an array <code>nums</code> of <strong>distinct</strong> positive integers. You need to sort the array in <strong>increasing</strong> order based on the sum of the digits of each number. If two numbers have the same digit sum, the <strong>smaller</strong> number appears first in the sorted order.</p> <p>Return the <strong>minimum</strong> number of swaps required to rearrange <code>nums</code> into this sorted order.</p> <p>A <strong>swap</strong> is defined as exchanging the values at two distinct positions in the array.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [37,100]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[3 + 7 = 10, 1 + 0 + 0 = 1] &rarr; [10, 1]</code></li> <li>Sort the integers based on digit sum: <code>[100, 37]</code>. Swap <code>37</code> with <code>100</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 1.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [22,14,33,7]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[2 + 2 = 4, 1 + 4 = 5, 3 + 3 = 6, 7 = 7] &rarr; [4, 5, 6, 7]</code></li> <li>Sort the integers based on digit sum: <code>[22, 14, 33, 7]</code>. The array is already sorted.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 0.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [18,43,34,16]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Compute the digit sum for each integer: <code>[1 + 8 = 9, 4 + 3 = 7, 3 + 4 = 7, 1 + 6 = 7] &rarr; [9, 7, 7, 7]</code></li> <li>Sort the integers based on digit sum: <code>[16, 34, 43, 18]</code>. Swap <code>18</code> with <code>16</code>, and swap <code>43</code> with <code>34</code> to obtain the sorted order.</li> <li>Thus, the minimum number of swaps required to rearrange <code>nums</code> is 2.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>nums</code> consists of <strong>distinct</strong> positive integers.</li> </ul>
Array; Hash Table; Sorting
TypeScript
function f(x: number): number { let s = 0; while (x !== 0) { s += x % 10; x = Math.floor(x / 10); } return s; } function minSwaps(nums: number[]): number { const n = nums.length; const arr: [number, number][] = new Array(n); for (let i = 0; i < n; i++) { arr[i] = [f(nums[i]), nums[i]]; } arr.sort((a, b) => (a[0] !== b[0] ? a[0] - b[0] : a[1] - b[1])); const d = new Map<number, number>(); for (let i = 0; i < n; i++) { d.set(arr[i][1], i); } const vis: boolean[] = new Array(n).fill(false); let ans = n; for (let i = 0; i < n; i++) { if (!vis[i]) { ans--; let j = i; while (!vis[j]) { vis[j] = true; j = d.get(nums[j])!; } } } return ans; }
3,552
Grid Teleportation Traversal
Medium
<p>You are given a 2D character grid <code>matrix</code> of size <code>m x n</code>, represented as an array of strings, where <code>matrix[i][j]</code> represents the cell at the intersection of the <code>i<sup>th</sup></code> row and <code>j<sup>th</sup></code> column. Each cell is one of the following:</p> <ul> <li><code>&#39;.&#39;</code> representing an empty cell.</li> <li><code>&#39;#&#39;</code> representing an obstacle.</li> <li>An uppercase letter (<code>&#39;A&#39;</code>-<code>&#39;Z&#39;</code>) representing a teleportation portal.</li> </ul> <p>You start at the top-left cell <code>(0, 0)</code>, and your goal is to reach the bottom-right cell <code>(m - 1, n - 1)</code>. You can move from the current cell to any adjacent cell (up, down, left, right) as long as the destination cell is within the grid bounds and is not an obstacle<strong>.</strong></p> <p>If you step on a cell containing a portal letter and you haven&#39;t used that portal letter before, you may instantly teleport to any other cell in the grid with the same letter. This teleportation does not count as a move, but each portal letter can be used<strong> at most </strong>once during your journey.</p> <p>Return the <strong>minimum</strong> number of moves required to reach the bottom-right cell. If it is not possible to reach the destination, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;A..&quot;,&quot;.A.&quot;,&quot;...&quot;]</span></p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/example04140.png" style="width: 151px; height: 151px;" /></p> <ul> <li>Before the first move, teleport from <code>(0, 0)</code> to <code>(1, 1)</code>.</li> <li>In the first move, move from <code>(1, 1)</code> to <code>(1, 2)</code>.</li> <li>In the second move, move from <code>(1, 2)</code> to <code>(2, 2)</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;.#...&quot;,&quot;.#.#.&quot;,&quot;.#.#.&quot;,&quot;...#.&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/ezgifcom-animated-gif-maker.gif" style="width: 251px; height: 201px;" /></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == matrix.length &lt;= 10<sup>3</sup></code></li> <li><code>1 &lt;= n == matrix[i].length &lt;= 10<sup>3</sup></code></li> <li><code>matrix[i][j]</code> is either <code>&#39;#&#39;</code>, <code>&#39;.&#39;</code>, or an uppercase English letter.</li> <li><code>matrix[0][0]</code> is not an obstacle.</li> </ul>
Breadth-First Search; Array; Hash Table; Matrix
C++
class Solution { public: int minMoves(vector<string>& matrix) { int m = matrix.size(), n = matrix[0].size(); unordered_map<char, vector<pair<int, int>>> g; for (int i = 0; i < m; ++i) for (int j = 0; j < n; ++j) { char c = matrix[i][j]; if (isalpha(c)) g[c].push_back({i, j}); } int dirs[5] = {-1, 0, 1, 0, -1}; int INF = numeric_limits<int>::max() / 2; vector<vector<int>> dist(m, vector<int>(n, INF)); dist[0][0] = 0; deque<pair<int, int>> q; q.push_back({0, 0}); while (!q.empty()) { auto [i, j] = q.front(); q.pop_front(); int d = dist[i][j]; if (i == m - 1 && j == n - 1) return d; char c = matrix[i][j]; if (g.count(c)) { for (auto [x, y] : g[c]) if (d < dist[x][y]) { dist[x][y] = d; q.push_front({x, y}); } g.erase(c); } for (int idx = 0; idx < 4; ++idx) { int x = i + dirs[idx], y = j + dirs[idx + 1]; if (0 <= x && x < m && 0 <= y && y < n && matrix[x][y] != '#' && d + 1 < dist[x][y]) { dist[x][y] = d + 1; q.push_back({x, y}); } } } return -1; } };
3,552
Grid Teleportation Traversal
Medium
<p>You are given a 2D character grid <code>matrix</code> of size <code>m x n</code>, represented as an array of strings, where <code>matrix[i][j]</code> represents the cell at the intersection of the <code>i<sup>th</sup></code> row and <code>j<sup>th</sup></code> column. Each cell is one of the following:</p> <ul> <li><code>&#39;.&#39;</code> representing an empty cell.</li> <li><code>&#39;#&#39;</code> representing an obstacle.</li> <li>An uppercase letter (<code>&#39;A&#39;</code>-<code>&#39;Z&#39;</code>) representing a teleportation portal.</li> </ul> <p>You start at the top-left cell <code>(0, 0)</code>, and your goal is to reach the bottom-right cell <code>(m - 1, n - 1)</code>. You can move from the current cell to any adjacent cell (up, down, left, right) as long as the destination cell is within the grid bounds and is not an obstacle<strong>.</strong></p> <p>If you step on a cell containing a portal letter and you haven&#39;t used that portal letter before, you may instantly teleport to any other cell in the grid with the same letter. This teleportation does not count as a move, but each portal letter can be used<strong> at most </strong>once during your journey.</p> <p>Return the <strong>minimum</strong> number of moves required to reach the bottom-right cell. If it is not possible to reach the destination, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;A..&quot;,&quot;.A.&quot;,&quot;...&quot;]</span></p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/example04140.png" style="width: 151px; height: 151px;" /></p> <ul> <li>Before the first move, teleport from <code>(0, 0)</code> to <code>(1, 1)</code>.</li> <li>In the first move, move from <code>(1, 1)</code> to <code>(1, 2)</code>.</li> <li>In the second move, move from <code>(1, 2)</code> to <code>(2, 2)</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;.#...&quot;,&quot;.#.#.&quot;,&quot;.#.#.&quot;,&quot;...#.&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/ezgifcom-animated-gif-maker.gif" style="width: 251px; height: 201px;" /></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == matrix.length &lt;= 10<sup>3</sup></code></li> <li><code>1 &lt;= n == matrix[i].length &lt;= 10<sup>3</sup></code></li> <li><code>matrix[i][j]</code> is either <code>&#39;#&#39;</code>, <code>&#39;.&#39;</code>, or an uppercase English letter.</li> <li><code>matrix[0][0]</code> is not an obstacle.</li> </ul>
Breadth-First Search; Array; Hash Table; Matrix
Go
type pair struct{ x, y int } func minMoves(matrix []string) int { m, n := len(matrix), len(matrix[0]) g := make(map[rune][]pair) for i := 0; i < m; i++ { for j, c := range matrix[i] { if unicode.IsLetter(c) { g[c] = append(g[c], pair{i, j}) } } } dirs := []int{-1, 0, 1, 0, -1} INF := 1 << 30 dist := make([][]int, m) for i := range dist { dist[i] = make([]int, n) for j := range dist[i] { dist[i][j] = INF } } dist[0][0] = 0 q := list.New() q.PushBack(pair{0, 0}) for q.Len() > 0 { cur := q.Remove(q.Front()).(pair) i, j := cur.x, cur.y d := dist[i][j] if i == m-1 && j == n-1 { return d } c := rune(matrix[i][j]) if v, ok := g[c]; ok { for _, p := range v { x, y := p.x, p.y if d < dist[x][y] { dist[x][y] = d q.PushFront(pair{x, y}) } } delete(g, c) } for idx := 0; idx < 4; idx++ { x, y := i+dirs[idx], j+dirs[idx+1] if 0 <= x && x < m && 0 <= y && y < n && matrix[x][y] != '#' && d+1 < dist[x][y] { dist[x][y] = d + 1 q.PushBack(pair{x, y}) } } } return -1 }
3,552
Grid Teleportation Traversal
Medium
<p>You are given a 2D character grid <code>matrix</code> of size <code>m x n</code>, represented as an array of strings, where <code>matrix[i][j]</code> represents the cell at the intersection of the <code>i<sup>th</sup></code> row and <code>j<sup>th</sup></code> column. Each cell is one of the following:</p> <ul> <li><code>&#39;.&#39;</code> representing an empty cell.</li> <li><code>&#39;#&#39;</code> representing an obstacle.</li> <li>An uppercase letter (<code>&#39;A&#39;</code>-<code>&#39;Z&#39;</code>) representing a teleportation portal.</li> </ul> <p>You start at the top-left cell <code>(0, 0)</code>, and your goal is to reach the bottom-right cell <code>(m - 1, n - 1)</code>. You can move from the current cell to any adjacent cell (up, down, left, right) as long as the destination cell is within the grid bounds and is not an obstacle<strong>.</strong></p> <p>If you step on a cell containing a portal letter and you haven&#39;t used that portal letter before, you may instantly teleport to any other cell in the grid with the same letter. This teleportation does not count as a move, but each portal letter can be used<strong> at most </strong>once during your journey.</p> <p>Return the <strong>minimum</strong> number of moves required to reach the bottom-right cell. If it is not possible to reach the destination, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;A..&quot;,&quot;.A.&quot;,&quot;...&quot;]</span></p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/example04140.png" style="width: 151px; height: 151px;" /></p> <ul> <li>Before the first move, teleport from <code>(0, 0)</code> to <code>(1, 1)</code>.</li> <li>In the first move, move from <code>(1, 1)</code> to <code>(1, 2)</code>.</li> <li>In the second move, move from <code>(1, 2)</code> to <code>(2, 2)</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;.#...&quot;,&quot;.#.#.&quot;,&quot;.#.#.&quot;,&quot;...#.&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/ezgifcom-animated-gif-maker.gif" style="width: 251px; height: 201px;" /></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == matrix.length &lt;= 10<sup>3</sup></code></li> <li><code>1 &lt;= n == matrix[i].length &lt;= 10<sup>3</sup></code></li> <li><code>matrix[i][j]</code> is either <code>&#39;#&#39;</code>, <code>&#39;.&#39;</code>, or an uppercase English letter.</li> <li><code>matrix[0][0]</code> is not an obstacle.</li> </ul>
Breadth-First Search; Array; Hash Table; Matrix
Java
class Solution { public int minMoves(String[] matrix) { int m = matrix.length, n = matrix[0].length(); Map<Character, List<int[]>> g = new HashMap<>(); for (int i = 0; i < m; i++) { String row = matrix[i]; for (int j = 0; j < n; j++) { char c = row.charAt(j); if (Character.isAlphabetic(c)) { g.computeIfAbsent(c, k -> new ArrayList<>()).add(new int[] {i, j}); } } } int[] dirs = {-1, 0, 1, 0, -1}; int INF = Integer.MAX_VALUE / 2; int[][] dist = new int[m][n]; for (int[] arr : dist) Arrays.fill(arr, INF); dist[0][0] = 0; Deque<int[]> q = new ArrayDeque<>(); q.add(new int[] {0, 0}); while (!q.isEmpty()) { int[] cur = q.pollFirst(); int i = cur[0], j = cur[1]; int d = dist[i][j]; if (i == m - 1 && j == n - 1) return d; char c = matrix[i].charAt(j); if (g.containsKey(c)) { for (int[] pos : g.get(c)) { int x = pos[0], y = pos[1]; if (d < dist[x][y]) { dist[x][y] = d; q.addFirst(new int[] {x, y}); } } g.remove(c); } for (int idx = 0; idx < 4; idx++) { int a = dirs[idx], b = dirs[idx + 1]; int x = i + a, y = j + b; if (0 <= x && x < m && 0 <= y && y < n && matrix[x].charAt(y) != '#' && d + 1 < dist[x][y]) { dist[x][y] = d + 1; q.addLast(new int[] {x, y}); } } } return -1; } }
3,552
Grid Teleportation Traversal
Medium
<p>You are given a 2D character grid <code>matrix</code> of size <code>m x n</code>, represented as an array of strings, where <code>matrix[i][j]</code> represents the cell at the intersection of the <code>i<sup>th</sup></code> row and <code>j<sup>th</sup></code> column. Each cell is one of the following:</p> <ul> <li><code>&#39;.&#39;</code> representing an empty cell.</li> <li><code>&#39;#&#39;</code> representing an obstacle.</li> <li>An uppercase letter (<code>&#39;A&#39;</code>-<code>&#39;Z&#39;</code>) representing a teleportation portal.</li> </ul> <p>You start at the top-left cell <code>(0, 0)</code>, and your goal is to reach the bottom-right cell <code>(m - 1, n - 1)</code>. You can move from the current cell to any adjacent cell (up, down, left, right) as long as the destination cell is within the grid bounds and is not an obstacle<strong>.</strong></p> <p>If you step on a cell containing a portal letter and you haven&#39;t used that portal letter before, you may instantly teleport to any other cell in the grid with the same letter. This teleportation does not count as a move, but each portal letter can be used<strong> at most </strong>once during your journey.</p> <p>Return the <strong>minimum</strong> number of moves required to reach the bottom-right cell. If it is not possible to reach the destination, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;A..&quot;,&quot;.A.&quot;,&quot;...&quot;]</span></p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/example04140.png" style="width: 151px; height: 151px;" /></p> <ul> <li>Before the first move, teleport from <code>(0, 0)</code> to <code>(1, 1)</code>.</li> <li>In the first move, move from <code>(1, 1)</code> to <code>(1, 2)</code>.</li> <li>In the second move, move from <code>(1, 2)</code> to <code>(2, 2)</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;.#...&quot;,&quot;.#.#.&quot;,&quot;.#.#.&quot;,&quot;...#.&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/ezgifcom-animated-gif-maker.gif" style="width: 251px; height: 201px;" /></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == matrix.length &lt;= 10<sup>3</sup></code></li> <li><code>1 &lt;= n == matrix[i].length &lt;= 10<sup>3</sup></code></li> <li><code>matrix[i][j]</code> is either <code>&#39;#&#39;</code>, <code>&#39;.&#39;</code>, or an uppercase English letter.</li> <li><code>matrix[0][0]</code> is not an obstacle.</li> </ul>
Breadth-First Search; Array; Hash Table; Matrix
Python
class Solution: def minMoves(self, matrix: List[str]) -> int: m, n = len(matrix), len(matrix[0]) g = defaultdict(list) for i, row in enumerate(matrix): for j, c in enumerate(row): if c.isalpha(): g[c].append((i, j)) dirs = (-1, 0, 1, 0, -1) dist = [[inf] * n for _ in range(m)] dist[0][0] = 0 q = deque([(0, 0)]) while q: i, j = q.popleft() d = dist[i][j] if i == m - 1 and j == n - 1: return d c = matrix[i][j] if c in g: for x, y in g[c]: if d < dist[x][y]: dist[x][y] = d q.appendleft((x, y)) del g[c] for a, b in pairwise(dirs): x, y = i + a, j + b if ( 0 <= x < m and 0 <= y < n and matrix[x][y] != "#" and d + 1 < dist[x][y] ): dist[x][y] = d + 1 q.append((x, y)) return -1
3,552
Grid Teleportation Traversal
Medium
<p>You are given a 2D character grid <code>matrix</code> of size <code>m x n</code>, represented as an array of strings, where <code>matrix[i][j]</code> represents the cell at the intersection of the <code>i<sup>th</sup></code> row and <code>j<sup>th</sup></code> column. Each cell is one of the following:</p> <ul> <li><code>&#39;.&#39;</code> representing an empty cell.</li> <li><code>&#39;#&#39;</code> representing an obstacle.</li> <li>An uppercase letter (<code>&#39;A&#39;</code>-<code>&#39;Z&#39;</code>) representing a teleportation portal.</li> </ul> <p>You start at the top-left cell <code>(0, 0)</code>, and your goal is to reach the bottom-right cell <code>(m - 1, n - 1)</code>. You can move from the current cell to any adjacent cell (up, down, left, right) as long as the destination cell is within the grid bounds and is not an obstacle<strong>.</strong></p> <p>If you step on a cell containing a portal letter and you haven&#39;t used that portal letter before, you may instantly teleport to any other cell in the grid with the same letter. This teleportation does not count as a move, but each portal letter can be used<strong> at most </strong>once during your journey.</p> <p>Return the <strong>minimum</strong> number of moves required to reach the bottom-right cell. If it is not possible to reach the destination, return <code>-1</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;A..&quot;,&quot;.A.&quot;,&quot;...&quot;]</span></p> <p><strong>Output:</strong> 2</p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/example04140.png" style="width: 151px; height: 151px;" /></p> <ul> <li>Before the first move, teleport from <code>(0, 0)</code> to <code>(1, 1)</code>.</li> <li>In the first move, move from <code>(1, 1)</code> to <code>(1, 2)</code>.</li> <li>In the second move, move from <code>(1, 2)</code> to <code>(2, 2)</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">matrix = [&quot;.#...&quot;,&quot;.#.#.&quot;,&quot;.#.#.&quot;,&quot;...#.&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3500-3599/3552.Grid%20Teleportation%20Traversal/images/ezgifcom-animated-gif-maker.gif" style="width: 251px; height: 201px;" /></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m == matrix.length &lt;= 10<sup>3</sup></code></li> <li><code>1 &lt;= n == matrix[i].length &lt;= 10<sup>3</sup></code></li> <li><code>matrix[i][j]</code> is either <code>&#39;#&#39;</code>, <code>&#39;.&#39;</code>, or an uppercase English letter.</li> <li><code>matrix[0][0]</code> is not an obstacle.</li> </ul>
Breadth-First Search; Array; Hash Table; Matrix
TypeScript
function minMoves(matrix: string[]): number { const m = matrix.length, n = matrix[0].length; const g = new Map<string, [number, number][]>(); for (let i = 0; i < m; i++) { for (let j = 0; j < n; j++) { const c = matrix[i][j]; if (/^[A-Za-z]$/.test(c)) { if (!g.has(c)) g.set(c, []); g.get(c)!.push([i, j]); } } } const dirs = [-1, 0, 1, 0, -1]; const INF = Number.MAX_SAFE_INTEGER; const dist: number[][] = Array.from({ length: m }, () => Array(n).fill(INF)); dist[0][0] = 0; const cap = m * n * 2 + 5; const dq = new Array<[number, number]>(cap); let l = cap >> 1, r = cap >> 1; const pushFront = (v: [number, number]) => { dq[--l] = v; }; const pushBack = (v: [number, number]) => { dq[r++] = v; }; const popFront = (): [number, number] => dq[l++]; const empty = () => l === r; pushBack([0, 0]); while (!empty()) { const [i, j] = popFront(); const d = dist[i][j]; if (i === m - 1 && j === n - 1) return d; const c = matrix[i][j]; if (g.has(c)) { for (const [x, y] of g.get(c)!) { if (d < dist[x][y]) { dist[x][y] = d; pushFront([x, y]); } } g.delete(c); } for (let idx = 0; idx < 4; idx++) { const x = i + dirs[idx], y = j + dirs[idx + 1]; if (0 <= x && x < m && 0 <= y && y < n && matrix[x][y] !== '#' && d + 1 < dist[x][y]) { dist[x][y] = d + 1; pushBack([x, y]); } } } return -1; }
3,554
Find Category Recommendation Pairs
Hard
<p>Table: <code>ProductPurchases</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | product_id | int | | quantity | int | +-------------+------+ (user_id, product_id) is the unique identifier for this table. Each row represents a purchase of a product by a user in a specific quantity. </pre> <p>Table: <code>ProductInfo</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | product_id | int | | category | varchar | | price | decimal | +-------------+---------+ product_id is the unique identifier for this table. Each row assigns a category and price to a product. </pre> <p>Amazon wants to understand shopping patterns across product categories. Write a solution to:</p> <ol> <li>Find all <strong>category pairs</strong> (where <code>category1</code> &lt; <code>category2</code>)</li> <li>For <strong>each category pair</strong>, determine the number of <strong>unique</strong> <strong>customers</strong> who purchased products from <strong>both</strong> categories</li> </ol> <p>A category pair is considered <strong>reportable</strong> if at least <code>3</code> different customers have purchased products from both categories.</p> <p>Return <em>the result table of reportable category pairs ordered by <strong>customer_count</strong> in <strong>descending</strong> order, and in case of a tie, by <strong>category1</strong> in <strong>ascending</strong> order lexicographically, and then by <strong>category2</strong> in <strong>ascending</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>ProductPurchases table:</p> <pre class="example-io"> +---------+------------+----------+ | user_id | product_id | quantity | +---------+------------+----------+ | 1 | 101 | 2 | | 1 | 102 | 1 | | 1 | 201 | 3 | | 1 | 301 | 1 | | 2 | 101 | 1 | | 2 | 102 | 2 | | 2 | 103 | 1 | | 2 | 201 | 5 | | 3 | 101 | 2 | | 3 | 103 | 1 | | 3 | 301 | 4 | | 3 | 401 | 2 | | 4 | 101 | 1 | | 4 | 201 | 3 | | 4 | 301 | 1 | | 4 | 401 | 2 | | 5 | 102 | 2 | | 5 | 103 | 1 | | 5 | 201 | 2 | | 5 | 202 | 3 | +---------+------------+----------+ </pre> <p>ProductInfo table:</p> <pre class="example-io"> +------------+-------------+-------+ | product_id | category | price | +------------+-------------+-------+ | 101 | Electronics | 100 | | 102 | Books | 20 | | 103 | Books | 35 | | 201 | Clothing | 45 | | 202 | Clothing | 60 | | 301 | Sports | 75 | | 401 | Kitchen | 50 | +------------+-------------+-------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------+-------------+----------------+ | category1 | category2 | customer_count | +-------------+-------------+----------------+ | Books | Clothing | 3 | | Books | Electronics | 3 | | Clothing | Electronics | 3 | | Electronics | Sports | 3 | +-------------+-------------+----------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li><strong>Books-Clothing</strong>: <ul> <li>User 1 purchased products from Books (102) and Clothing (201)</li> <li>User 2 purchased products from Books (102, 103) and Clothing (201)</li> <li>User 5 purchased products from Books (102, 103) and Clothing (201, 202)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Books-Electronics</strong>: <ul> <li>User 1 purchased products from Books (102) and Electronics (101)</li> <li>User 2 purchased products from Books (102, 103) and Electronics (101)</li> <li>User 3 purchased products from Books (103) and Electronics (101)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Clothing-Electronics</strong>: <ul> <li>User 1 purchased products from Clothing (201) and Electronics (101)</li> <li>User 2 purchased products from Clothing (201) and Electronics (101)</li> <li>User 4 purchased products from Clothing (201) and Electronics (101)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Electronics-Sports</strong>: <ul> <li>User 1 purchased products from Electronics (101) and Sports (301)</li> <li>User 3 purchased products from Electronics (101) and Sports (301)</li> <li>User 4 purchased products from Electronics (101) and Sports (301)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li>Other category pairs like Clothing-Sports (only 2 customers: Users 1 and 4) and Books-Kitchen (only 1 customer: User 3) have fewer than 3 shared customers and are not included in the result.</li> </ul> <p>The result is ordered by customer_count in descending order. Since all pairs have the same customer_count of 3, they are ordered by category1 (then category2) in ascending order.</p> </div>
Database
Python
import pandas as pd def find_category_recommendation_pairs( product_purchases: pd.DataFrame, product_info: pd.DataFrame ) -> pd.DataFrame: df = product_purchases[["user_id", "product_id"]].merge( product_info[["product_id", "category"]], on="product_id", how="inner" ) user_category = df.drop_duplicates(subset=["user_id", "category"]) pair_per_user = ( user_category.merge(user_category, on="user_id") .query("category_x < category_y") .rename(columns={"category_x": "category1", "category_y": "category2"}) ) pair_counts = ( pair_per_user.groupby(["category1", "category2"])["user_id"] .nunique() .reset_index(name="customer_count") ) result = ( pair_counts.query("customer_count >= 3") .sort_values( ["customer_count", "category1", "category2"], ascending=[False, True, True] ) .reset_index(drop=True) ) return result
3,554
Find Category Recommendation Pairs
Hard
<p>Table: <code>ProductPurchases</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | user_id | int | | product_id | int | | quantity | int | +-------------+------+ (user_id, product_id) is the unique identifier for this table. Each row represents a purchase of a product by a user in a specific quantity. </pre> <p>Table: <code>ProductInfo</code></p> <pre> +-------------+---------+ | Column Name | Type | +-------------+---------+ | product_id | int | | category | varchar | | price | decimal | +-------------+---------+ product_id is the unique identifier for this table. Each row assigns a category and price to a product. </pre> <p>Amazon wants to understand shopping patterns across product categories. Write a solution to:</p> <ol> <li>Find all <strong>category pairs</strong> (where <code>category1</code> &lt; <code>category2</code>)</li> <li>For <strong>each category pair</strong>, determine the number of <strong>unique</strong> <strong>customers</strong> who purchased products from <strong>both</strong> categories</li> </ol> <p>A category pair is considered <strong>reportable</strong> if at least <code>3</code> different customers have purchased products from both categories.</p> <p>Return <em>the result table of reportable category pairs ordered by <strong>customer_count</strong> in <strong>descending</strong> order, and in case of a tie, by <strong>category1</strong> in <strong>ascending</strong> order lexicographically, and then by <strong>category2</strong> in <strong>ascending</strong> order.</em></p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>ProductPurchases table:</p> <pre class="example-io"> +---------+------------+----------+ | user_id | product_id | quantity | +---------+------------+----------+ | 1 | 101 | 2 | | 1 | 102 | 1 | | 1 | 201 | 3 | | 1 | 301 | 1 | | 2 | 101 | 1 | | 2 | 102 | 2 | | 2 | 103 | 1 | | 2 | 201 | 5 | | 3 | 101 | 2 | | 3 | 103 | 1 | | 3 | 301 | 4 | | 3 | 401 | 2 | | 4 | 101 | 1 | | 4 | 201 | 3 | | 4 | 301 | 1 | | 4 | 401 | 2 | | 5 | 102 | 2 | | 5 | 103 | 1 | | 5 | 201 | 2 | | 5 | 202 | 3 | +---------+------------+----------+ </pre> <p>ProductInfo table:</p> <pre class="example-io"> +------------+-------------+-------+ | product_id | category | price | +------------+-------------+-------+ | 101 | Electronics | 100 | | 102 | Books | 20 | | 103 | Books | 35 | | 201 | Clothing | 45 | | 202 | Clothing | 60 | | 301 | Sports | 75 | | 401 | Kitchen | 50 | +------------+-------------+-------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------+-------------+----------------+ | category1 | category2 | customer_count | +-------------+-------------+----------------+ | Books | Clothing | 3 | | Books | Electronics | 3 | | Clothing | Electronics | 3 | | Electronics | Sports | 3 | +-------------+-------------+----------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li><strong>Books-Clothing</strong>: <ul> <li>User 1 purchased products from Books (102) and Clothing (201)</li> <li>User 2 purchased products from Books (102, 103) and Clothing (201)</li> <li>User 5 purchased products from Books (102, 103) and Clothing (201, 202)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Books-Electronics</strong>: <ul> <li>User 1 purchased products from Books (102) and Electronics (101)</li> <li>User 2 purchased products from Books (102, 103) and Electronics (101)</li> <li>User 3 purchased products from Books (103) and Electronics (101)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Clothing-Electronics</strong>: <ul> <li>User 1 purchased products from Clothing (201) and Electronics (101)</li> <li>User 2 purchased products from Clothing (201) and Electronics (101)</li> <li>User 4 purchased products from Clothing (201) and Electronics (101)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li><strong>Electronics-Sports</strong>: <ul> <li>User 1 purchased products from Electronics (101) and Sports (301)</li> <li>User 3 purchased products from Electronics (101) and Sports (301)</li> <li>User 4 purchased products from Electronics (101) and Sports (301)</li> <li>Total: 3 customers purchased from both categories</li> </ul> </li> <li>Other category pairs like Clothing-Sports (only 2 customers: Users 1 and 4) and Books-Kitchen (only 1 customer: User 3) have fewer than 3 shared customers and are not included in the result.</li> </ul> <p>The result is ordered by customer_count in descending order. Since all pairs have the same customer_count of 3, they are ordered by category1 (then category2) in ascending order.</p> </div>
Database
SQL
# Write your MySQL query statement below WITH user_category AS ( SELECT DISTINCT user_id, category FROM ProductPurchases JOIN ProductInfo USING (product_id) ), pair_per_user AS ( SELECT a.user_id, a.category AS category1, b.category AS category2 FROM user_category AS a JOIN user_category AS b ON a.user_id = b.user_id AND a.category < b.category ) SELECT category1, category2, COUNT(DISTINCT user_id) AS customer_count FROM pair_per_user GROUP BY 1, 2 HAVING customer_count >= 3 ORDER BY 3 DESC, 1, 2;
3,555
Smallest Subarray to Sort in Every Sliding Window
Medium
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>.</p> <p>For each contiguous <span data-keyword="subarray">subarray</span> of length <code>k</code>, determine the <strong>minimum</strong> length of a continuous segment that must be sorted so that the entire window becomes <strong>non‑decreasing</strong>; if the window is already sorted, its required length is zero.</p> <p>Return an array of length <code>n &minus; k + 1</code> where each element corresponds to the answer for its window.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2,4,5], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...2] = [1, 3, 2]</code>. Sort <code>[3, 2]</code> to get <code>[1, 2, 3]</code>, the answer is 2.</li> <li><code>nums[1...3] = [3, 2, 4]</code>. Sort <code>[3, 2]</code> to get <code>[2, 3, 4]</code>, the answer is 2.</li> <li><code>nums[2...4] = [2, 4, 5]</code> is already sorted, so the answer is 0.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,4,3,2,1], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[4,4]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...3] = [5, 4, 3, 2]</code>. The whole subarray must be sorted, so the answer is 4.</li> <li><code>nums[1...4] = [4, 3, 2, 1]</code>. The whole subarray must be sorted, so the answer is 4.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= nums.length</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Stack; Greedy; Array; Two Pointers; Sorting; Monotonic Stack
C++
class Solution { public: vector<int> minSubarraySort(vector<int>& nums, int k) { const int inf = 1 << 30; int n = nums.size(); auto f = [&](int i, int j) -> int { int mi = inf, mx = -inf; int l = -1, r = -1; for (int k = i; k <= j; ++k) { if (nums[k] < mx) { r = k; } else { mx = nums[k]; } int p = j - k + i; if (nums[p] > mi) { l = p; } else { mi = nums[p]; } } return r == -1 ? 0 : r - l + 1; }; vector<int> ans; for (int i = 0; i < n - k + 1; ++i) { ans.push_back(f(i, i + k - 1)); } return ans; } };
3,555
Smallest Subarray to Sort in Every Sliding Window
Medium
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>.</p> <p>For each contiguous <span data-keyword="subarray">subarray</span> of length <code>k</code>, determine the <strong>minimum</strong> length of a continuous segment that must be sorted so that the entire window becomes <strong>non‑decreasing</strong>; if the window is already sorted, its required length is zero.</p> <p>Return an array of length <code>n &minus; k + 1</code> where each element corresponds to the answer for its window.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2,4,5], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...2] = [1, 3, 2]</code>. Sort <code>[3, 2]</code> to get <code>[1, 2, 3]</code>, the answer is 2.</li> <li><code>nums[1...3] = [3, 2, 4]</code>. Sort <code>[3, 2]</code> to get <code>[2, 3, 4]</code>, the answer is 2.</li> <li><code>nums[2...4] = [2, 4, 5]</code> is already sorted, so the answer is 0.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,4,3,2,1], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[4,4]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...3] = [5, 4, 3, 2]</code>. The whole subarray must be sorted, so the answer is 4.</li> <li><code>nums[1...4] = [4, 3, 2, 1]</code>. The whole subarray must be sorted, so the answer is 4.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= nums.length</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Stack; Greedy; Array; Two Pointers; Sorting; Monotonic Stack
Go
func minSubarraySort(nums []int, k int) []int { const inf = 1 << 30 n := len(nums) f := func(i, j int) int { mi := inf mx := -inf l, r := -1, -1 for p := i; p <= j; p++ { if nums[p] < mx { r = p } else { mx = nums[p] } q := j - p + i if nums[q] > mi { l = q } else { mi = nums[q] } } if r == -1 { return 0 } return r - l + 1 } ans := make([]int, 0, n-k+1) for i := 0; i <= n-k; i++ { ans = append(ans, f(i, i+k-1)) } return ans }
3,555
Smallest Subarray to Sort in Every Sliding Window
Medium
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>.</p> <p>For each contiguous <span data-keyword="subarray">subarray</span> of length <code>k</code>, determine the <strong>minimum</strong> length of a continuous segment that must be sorted so that the entire window becomes <strong>non‑decreasing</strong>; if the window is already sorted, its required length is zero.</p> <p>Return an array of length <code>n &minus; k + 1</code> where each element corresponds to the answer for its window.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2,4,5], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...2] = [1, 3, 2]</code>. Sort <code>[3, 2]</code> to get <code>[1, 2, 3]</code>, the answer is 2.</li> <li><code>nums[1...3] = [3, 2, 4]</code>. Sort <code>[3, 2]</code> to get <code>[2, 3, 4]</code>, the answer is 2.</li> <li><code>nums[2...4] = [2, 4, 5]</code> is already sorted, so the answer is 0.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,4,3,2,1], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[4,4]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...3] = [5, 4, 3, 2]</code>. The whole subarray must be sorted, so the answer is 4.</li> <li><code>nums[1...4] = [4, 3, 2, 1]</code>. The whole subarray must be sorted, so the answer is 4.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= nums.length</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Stack; Greedy; Array; Two Pointers; Sorting; Monotonic Stack
Java
class Solution { private int[] nums; private final int inf = 1 << 30; public int[] minSubarraySort(int[] nums, int k) { this.nums = nums; int n = nums.length; int[] ans = new int[n - k + 1]; for (int i = 0; i < n - k + 1; ++i) { ans[i] = f(i, i + k - 1); } return ans; } private int f(int i, int j) { int mi = inf, mx = -inf; int l = -1, r = -1; for (int k = i; k <= j; ++k) { if (nums[k] < mx) { r = k; } else { mx = nums[k]; } int p = j - k + i; if (nums[p] > mi) { l = p; } else { mi = nums[p]; } } return r == -1 ? 0 : r - l + 1; } }
3,555
Smallest Subarray to Sort in Every Sliding Window
Medium
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>.</p> <p>For each contiguous <span data-keyword="subarray">subarray</span> of length <code>k</code>, determine the <strong>minimum</strong> length of a continuous segment that must be sorted so that the entire window becomes <strong>non‑decreasing</strong>; if the window is already sorted, its required length is zero.</p> <p>Return an array of length <code>n &minus; k + 1</code> where each element corresponds to the answer for its window.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2,4,5], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...2] = [1, 3, 2]</code>. Sort <code>[3, 2]</code> to get <code>[1, 2, 3]</code>, the answer is 2.</li> <li><code>nums[1...3] = [3, 2, 4]</code>. Sort <code>[3, 2]</code> to get <code>[2, 3, 4]</code>, the answer is 2.</li> <li><code>nums[2...4] = [2, 4, 5]</code> is already sorted, so the answer is 0.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,4,3,2,1], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[4,4]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...3] = [5, 4, 3, 2]</code>. The whole subarray must be sorted, so the answer is 4.</li> <li><code>nums[1...4] = [4, 3, 2, 1]</code>. The whole subarray must be sorted, so the answer is 4.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= nums.length</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Stack; Greedy; Array; Two Pointers; Sorting; Monotonic Stack
Python
class Solution: def minSubarraySort(self, nums: List[int], k: int) -> List[int]: def f(i: int, j: int) -> int: mi, mx = inf, -inf l = r = -1 for k in range(i, j + 1): if mx > nums[k]: r = k else: mx = nums[k] p = j - k + i if mi < nums[p]: l = p else: mi = nums[p] return 0 if r == -1 else r - l + 1 n = len(nums) return [f(i, i + k - 1) for i in range(n - k + 1)]
3,555
Smallest Subarray to Sort in Every Sliding Window
Medium
<p>You are given an integer array <code>nums</code> and an integer <code>k</code>.</p> <p>For each contiguous <span data-keyword="subarray">subarray</span> of length <code>k</code>, determine the <strong>minimum</strong> length of a continuous segment that must be sorted so that the entire window becomes <strong>non‑decreasing</strong>; if the window is already sorted, its required length is zero.</p> <p>Return an array of length <code>n &minus; k + 1</code> where each element corresponds to the answer for its window.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,3,2,4,5], k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,0]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...2] = [1, 3, 2]</code>. Sort <code>[3, 2]</code> to get <code>[1, 2, 3]</code>, the answer is 2.</li> <li><code>nums[1...3] = [3, 2, 4]</code>. Sort <code>[3, 2]</code> to get <code>[2, 3, 4]</code>, the answer is 2.</li> <li><code>nums[2...4] = [2, 4, 5]</code> is already sorted, so the answer is 0.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,4,3,2,1], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[4,4]</span></p> <p><strong>Explanation:</strong></p> <ul> <li><code>nums[0...3] = [5, 4, 3, 2]</code>. The whole subarray must be sorted, so the answer is 4.</li> <li><code>nums[1...4] = [4, 3, 2, 1]</code>. The whole subarray must be sorted, so the answer is 4.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= nums.length</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Stack; Greedy; Array; Two Pointers; Sorting; Monotonic Stack
TypeScript
function minSubarraySort(nums: number[], k: number): number[] { const inf = Infinity; const n = nums.length; const f = (i: number, j: number): number => { let mi = inf; let mx = -inf; let l = -1, r = -1; for (let p = i; p <= j; ++p) { if (nums[p] < mx) { r = p; } else { mx = nums[p]; } const q = j - p + i; if (nums[q] > mi) { l = q; } else { mi = nums[q]; } } return r === -1 ? 0 : r - l + 1; }; const ans: number[] = []; for (let i = 0; i <= n - k; ++i) { ans.push(f(i, i + k - 1)); } return ans; }
3,556
Sum of Largest Prime Substrings
Medium
<p data-end="157" data-start="30">Given a string <code>s</code>, find the sum of the <strong>3 largest unique <span data-keyword="prime-number">prime numbers</span></strong> that can be formed using any of its<strong> <span data-keyword="substring">substrings</span></strong>.</p> <p data-end="269" data-start="166">Return the <strong>sum</strong> of the three largest unique prime numbers that can be formed. If fewer than three exist, return the sum of <strong>all</strong> available primes. If no prime numbers can be formed, return 0.</p> <p data-end="370" data-is-last-node="" data-is-only-node="" data-start="271"><strong data-end="280" data-start="271">Note:</strong> Each prime number should be counted only <strong>once</strong>, even if it appears in <strong>multiple</strong> substrings. Additionally, when converting a substring to an integer, any leading zeros are ignored.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;12234&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1469</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="136" data-start="16">The unique prime numbers formed from the substrings of <code>&quot;12234&quot;</code> are 2, 3, 23, 223, and 1223.</li> <li data-end="226" data-start="137">The 3 largest primes are 1223, 223, and 23. Their sum is 1469.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;111&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">11</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="339" data-start="244">The unique prime number formed from the substrings of <code>&quot;111&quot;</code> is 11.</li> <li data-end="412" data-is-last-node="" data-start="340">Since there is only one prime number, the sum is 11.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li data-end="39" data-start="18"><code>1 &lt;= s.length &lt;= 10</code></li> <li data-end="68" data-is-last-node="" data-start="40"><code>s</code> consists of only digits.</li> </ul>
Hash Table; Math; String; Number Theory; Sorting
C++
class Solution { public: long long sumOfLargestPrimes(string s) { unordered_set<long long> st; int n = s.size(); for (int i = 0; i < n; ++i) { long long x = 0; for (int j = i; j < n; ++j) { x = x * 10 + (s[j] - '0'); if (is_prime(x)) { st.insert(x); } } } vector<long long> sorted(st.begin(), st.end()); sort(sorted.begin(), sorted.end()); long long ans = 0; int cnt = 0; for (int i = (int) sorted.size() - 1; i >= 0 && cnt < 3; --i, ++cnt) { ans += sorted[i]; } return ans; } private: bool is_prime(long long x) { if (x < 2) return false; for (long long i = 2; i * i <= x; ++i) { if (x % i == 0) return false; } return true; } };
3,556
Sum of Largest Prime Substrings
Medium
<p data-end="157" data-start="30">Given a string <code>s</code>, find the sum of the <strong>3 largest unique <span data-keyword="prime-number">prime numbers</span></strong> that can be formed using any of its<strong> <span data-keyword="substring">substrings</span></strong>.</p> <p data-end="269" data-start="166">Return the <strong>sum</strong> of the three largest unique prime numbers that can be formed. If fewer than three exist, return the sum of <strong>all</strong> available primes. If no prime numbers can be formed, return 0.</p> <p data-end="370" data-is-last-node="" data-is-only-node="" data-start="271"><strong data-end="280" data-start="271">Note:</strong> Each prime number should be counted only <strong>once</strong>, even if it appears in <strong>multiple</strong> substrings. Additionally, when converting a substring to an integer, any leading zeros are ignored.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;12234&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1469</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="136" data-start="16">The unique prime numbers formed from the substrings of <code>&quot;12234&quot;</code> are 2, 3, 23, 223, and 1223.</li> <li data-end="226" data-start="137">The 3 largest primes are 1223, 223, and 23. Their sum is 1469.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;111&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">11</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="339" data-start="244">The unique prime number formed from the substrings of <code>&quot;111&quot;</code> is 11.</li> <li data-end="412" data-is-last-node="" data-start="340">Since there is only one prime number, the sum is 11.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li data-end="39" data-start="18"><code>1 &lt;= s.length &lt;= 10</code></li> <li data-end="68" data-is-last-node="" data-start="40"><code>s</code> consists of only digits.</li> </ul>
Hash Table; Math; String; Number Theory; Sorting
Go
func sumOfLargestPrimes(s string) (ans int64) { st := make(map[int64]struct{}) n := len(s) for i := 0; i < n; i++ { var x int64 = 0 for j := i; j < n; j++ { x = x*10 + int64(s[j]-'0') if isPrime(x) { st[x] = struct{}{} } } } nums := make([]int64, 0, len(st)) for num := range st { nums = append(nums, num) } sort.Slice(nums, func(i, j int) bool { return nums[i] < nums[j] }) for i := len(nums) - 1; i >= 0 && len(nums)-i <= 3; i-- { ans += nums[i] } return } func isPrime(x int64) bool { if x < 2 { return false } sqrtX := int64(math.Sqrt(float64(x))) for i := int64(2); i <= sqrtX; i++ { if x%i == 0 { return false } } return true }
3,556
Sum of Largest Prime Substrings
Medium
<p data-end="157" data-start="30">Given a string <code>s</code>, find the sum of the <strong>3 largest unique <span data-keyword="prime-number">prime numbers</span></strong> that can be formed using any of its<strong> <span data-keyword="substring">substrings</span></strong>.</p> <p data-end="269" data-start="166">Return the <strong>sum</strong> of the three largest unique prime numbers that can be formed. If fewer than three exist, return the sum of <strong>all</strong> available primes. If no prime numbers can be formed, return 0.</p> <p data-end="370" data-is-last-node="" data-is-only-node="" data-start="271"><strong data-end="280" data-start="271">Note:</strong> Each prime number should be counted only <strong>once</strong>, even if it appears in <strong>multiple</strong> substrings. Additionally, when converting a substring to an integer, any leading zeros are ignored.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;12234&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1469</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="136" data-start="16">The unique prime numbers formed from the substrings of <code>&quot;12234&quot;</code> are 2, 3, 23, 223, and 1223.</li> <li data-end="226" data-start="137">The 3 largest primes are 1223, 223, and 23. Their sum is 1469.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;111&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">11</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="339" data-start="244">The unique prime number formed from the substrings of <code>&quot;111&quot;</code> is 11.</li> <li data-end="412" data-is-last-node="" data-start="340">Since there is only one prime number, the sum is 11.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li data-end="39" data-start="18"><code>1 &lt;= s.length &lt;= 10</code></li> <li data-end="68" data-is-last-node="" data-start="40"><code>s</code> consists of only digits.</li> </ul>
Hash Table; Math; String; Number Theory; Sorting
Java
class Solution { public long sumOfLargestPrimes(String s) { Set<Long> st = new HashSet<>(); int n = s.length(); for (int i = 0; i < n; i++) { long x = 0; for (int j = i; j < n; j++) { x = x * 10 + (s.charAt(j) - '0'); if (is_prime(x)) { st.add(x); } } } List<Long> sorted = new ArrayList<>(st); Collections.sort(sorted); long ans = 0; int start = Math.max(0, sorted.size() - 3); for (int idx = start; idx < sorted.size(); idx++) { ans += sorted.get(idx); } return ans; } private boolean is_prime(long x) { if (x < 2) return false; for (long i = 2; i * i <= x; i++) { if (x % i == 0) return false; } return true; } }
3,556
Sum of Largest Prime Substrings
Medium
<p data-end="157" data-start="30">Given a string <code>s</code>, find the sum of the <strong>3 largest unique <span data-keyword="prime-number">prime numbers</span></strong> that can be formed using any of its<strong> <span data-keyword="substring">substrings</span></strong>.</p> <p data-end="269" data-start="166">Return the <strong>sum</strong> of the three largest unique prime numbers that can be formed. If fewer than three exist, return the sum of <strong>all</strong> available primes. If no prime numbers can be formed, return 0.</p> <p data-end="370" data-is-last-node="" data-is-only-node="" data-start="271"><strong data-end="280" data-start="271">Note:</strong> Each prime number should be counted only <strong>once</strong>, even if it appears in <strong>multiple</strong> substrings. Additionally, when converting a substring to an integer, any leading zeros are ignored.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;12234&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1469</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="136" data-start="16">The unique prime numbers formed from the substrings of <code>&quot;12234&quot;</code> are 2, 3, 23, 223, and 1223.</li> <li data-end="226" data-start="137">The 3 largest primes are 1223, 223, and 23. Their sum is 1469.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;111&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">11</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="339" data-start="244">The unique prime number formed from the substrings of <code>&quot;111&quot;</code> is 11.</li> <li data-end="412" data-is-last-node="" data-start="340">Since there is only one prime number, the sum is 11.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li data-end="39" data-start="18"><code>1 &lt;= s.length &lt;= 10</code></li> <li data-end="68" data-is-last-node="" data-start="40"><code>s</code> consists of only digits.</li> </ul>
Hash Table; Math; String; Number Theory; Sorting
Python
class Solution: def sumOfLargestPrimes(self, s: str) -> int: def is_prime(x: int) -> bool: if x < 2: return False return all(x % i for i in range(2, int(sqrt(x)) + 1)) st = set() n = len(s) for i in range(n): x = 0 for j in range(i, n): x = x * 10 + int(s[j]) if is_prime(x): st.add(x) return sum(sorted(st)[-3:])
3,556
Sum of Largest Prime Substrings
Medium
<p data-end="157" data-start="30">Given a string <code>s</code>, find the sum of the <strong>3 largest unique <span data-keyword="prime-number">prime numbers</span></strong> that can be formed using any of its<strong> <span data-keyword="substring">substrings</span></strong>.</p> <p data-end="269" data-start="166">Return the <strong>sum</strong> of the three largest unique prime numbers that can be formed. If fewer than three exist, return the sum of <strong>all</strong> available primes. If no prime numbers can be formed, return 0.</p> <p data-end="370" data-is-last-node="" data-is-only-node="" data-start="271"><strong data-end="280" data-start="271">Note:</strong> Each prime number should be counted only <strong>once</strong>, even if it appears in <strong>multiple</strong> substrings. Additionally, when converting a substring to an integer, any leading zeros are ignored.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;12234&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1469</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="136" data-start="16">The unique prime numbers formed from the substrings of <code>&quot;12234&quot;</code> are 2, 3, 23, 223, and 1223.</li> <li data-end="226" data-start="137">The 3 largest primes are 1223, 223, and 23. Their sum is 1469.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;111&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">11</span></p> <p><strong>Explanation:</strong></p> <ul> <li data-end="339" data-start="244">The unique prime number formed from the substrings of <code>&quot;111&quot;</code> is 11.</li> <li data-end="412" data-is-last-node="" data-start="340">Since there is only one prime number, the sum is 11.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li data-end="39" data-start="18"><code>1 &lt;= s.length &lt;= 10</code></li> <li data-end="68" data-is-last-node="" data-start="40"><code>s</code> consists of only digits.</li> </ul>
Hash Table; Math; String; Number Theory; Sorting
TypeScript
function sumOfLargestPrimes(s: string): number { const st = new Set<number>(); const n = s.length; for (let i = 0; i < n; i++) { let x = 0; for (let j = i; j < n; j++) { x = x * 10 + Number(s[j]); if (isPrime(x)) { st.add(x); } } } const sorted = Array.from(st).sort((a, b) => a - b); const topThree = sorted.slice(-3); return topThree.reduce((sum, val) => sum + val, 0); } function isPrime(x: number): boolean { if (x < 2) return false; for (let i = 2; i * i <= x; i++) { if (x % i === 0) return false; } return true; }
3,560
Find Minimum Log Transportation Cost
Easy
<p>You are given integers <code>n</code>, <code>m</code>, and <code>k</code>.</p> <p>There are two logs of lengths <code>n</code> and <code>m</code> units, which need to be transported in three trucks where each truck can carry one log with length <strong>at most</strong> <code>k</code> units.</p> <p>You may cut the logs into smaller pieces, where the cost of cutting a log of length <code>x</code> into logs of length <code>len1</code> and <code>len2</code> is <code>cost = len1 * len2</code> such that <code>len1 + len2 = x</code>.</p> <p>Return the <strong>minimum total cost</strong> to distribute the logs onto the trucks. If the logs don&#39;t need to be cut, the total cost is 0.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 6, m = 5, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>Cut the log with length 6 into logs with length 1 and 5, at a cost equal to <code>1 * 5 == 5</code>. Now the three logs of length 1, 5, and 5 can fit in one truck each.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, m = 4, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>The two logs can fit in the trucks already, hence we don&#39;t need to cut the logs.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= k &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n, m &lt;= 2 * k</code></li> <li>The input is generated such that it is always possible to transport the logs.</li> </ul>
Math
C++
class Solution { public: long long minCuttingCost(int n, int m, int k) { int x = max(n, m); return x <= k ? 0 : 1LL * k * (x - k); } };
3,560
Find Minimum Log Transportation Cost
Easy
<p>You are given integers <code>n</code>, <code>m</code>, and <code>k</code>.</p> <p>There are two logs of lengths <code>n</code> and <code>m</code> units, which need to be transported in three trucks where each truck can carry one log with length <strong>at most</strong> <code>k</code> units.</p> <p>You may cut the logs into smaller pieces, where the cost of cutting a log of length <code>x</code> into logs of length <code>len1</code> and <code>len2</code> is <code>cost = len1 * len2</code> such that <code>len1 + len2 = x</code>.</p> <p>Return the <strong>minimum total cost</strong> to distribute the logs onto the trucks. If the logs don&#39;t need to be cut, the total cost is 0.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 6, m = 5, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>Cut the log with length 6 into logs with length 1 and 5, at a cost equal to <code>1 * 5 == 5</code>. Now the three logs of length 1, 5, and 5 can fit in one truck each.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, m = 4, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>The two logs can fit in the trucks already, hence we don&#39;t need to cut the logs.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= k &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n, m &lt;= 2 * k</code></li> <li>The input is generated such that it is always possible to transport the logs.</li> </ul>
Math
Go
func minCuttingCost(n int, m int, k int) int64 { x := max(n, m) if x <= k { return 0 } return int64(k * (x - k)) }
3,560
Find Minimum Log Transportation Cost
Easy
<p>You are given integers <code>n</code>, <code>m</code>, and <code>k</code>.</p> <p>There are two logs of lengths <code>n</code> and <code>m</code> units, which need to be transported in three trucks where each truck can carry one log with length <strong>at most</strong> <code>k</code> units.</p> <p>You may cut the logs into smaller pieces, where the cost of cutting a log of length <code>x</code> into logs of length <code>len1</code> and <code>len2</code> is <code>cost = len1 * len2</code> such that <code>len1 + len2 = x</code>.</p> <p>Return the <strong>minimum total cost</strong> to distribute the logs onto the trucks. If the logs don&#39;t need to be cut, the total cost is 0.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 6, m = 5, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>Cut the log with length 6 into logs with length 1 and 5, at a cost equal to <code>1 * 5 == 5</code>. Now the three logs of length 1, 5, and 5 can fit in one truck each.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, m = 4, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>The two logs can fit in the trucks already, hence we don&#39;t need to cut the logs.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= k &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n, m &lt;= 2 * k</code></li> <li>The input is generated such that it is always possible to transport the logs.</li> </ul>
Math
Java
class Solution { public long minCuttingCost(int n, int m, int k) { int x = Math.max(n, m); return x <= k ? 0 : 1L * k * (x - k); } }
3,560
Find Minimum Log Transportation Cost
Easy
<p>You are given integers <code>n</code>, <code>m</code>, and <code>k</code>.</p> <p>There are two logs of lengths <code>n</code> and <code>m</code> units, which need to be transported in three trucks where each truck can carry one log with length <strong>at most</strong> <code>k</code> units.</p> <p>You may cut the logs into smaller pieces, where the cost of cutting a log of length <code>x</code> into logs of length <code>len1</code> and <code>len2</code> is <code>cost = len1 * len2</code> such that <code>len1 + len2 = x</code>.</p> <p>Return the <strong>minimum total cost</strong> to distribute the logs onto the trucks. If the logs don&#39;t need to be cut, the total cost is 0.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 6, m = 5, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>Cut the log with length 6 into logs with length 1 and 5, at a cost equal to <code>1 * 5 == 5</code>. Now the three logs of length 1, 5, and 5 can fit in one truck each.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, m = 4, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>The two logs can fit in the trucks already, hence we don&#39;t need to cut the logs.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= k &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n, m &lt;= 2 * k</code></li> <li>The input is generated such that it is always possible to transport the logs.</li> </ul>
Math
Python
class Solution: def minCuttingCost(self, n: int, m: int, k: int) -> int: x = max(n, m) return 0 if x <= k else k * (x - k)
3,560
Find Minimum Log Transportation Cost
Easy
<p>You are given integers <code>n</code>, <code>m</code>, and <code>k</code>.</p> <p>There are two logs of lengths <code>n</code> and <code>m</code> units, which need to be transported in three trucks where each truck can carry one log with length <strong>at most</strong> <code>k</code> units.</p> <p>You may cut the logs into smaller pieces, where the cost of cutting a log of length <code>x</code> into logs of length <code>len1</code> and <code>len2</code> is <code>cost = len1 * len2</code> such that <code>len1 + len2 = x</code>.</p> <p>Return the <strong>minimum total cost</strong> to distribute the logs onto the trucks. If the logs don&#39;t need to be cut, the total cost is 0.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 6, m = 5, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>Cut the log with length 6 into logs with length 1 and 5, at a cost equal to <code>1 * 5 == 5</code>. Now the three logs of length 1, 5, and 5 can fit in one truck each.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 4, m = 4, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>The two logs can fit in the trucks already, hence we don&#39;t need to cut the logs.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= k &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= n, m &lt;= 2 * k</code></li> <li>The input is generated such that it is always possible to transport the logs.</li> </ul>
Math
TypeScript
function minCuttingCost(n: number, m: number, k: number): number { const x = Math.max(n, m); return x <= k ? 0 : k * (x - k); }
3,561
Resulting String After Adjacent Removals
Medium
<p>You are given a string <code>s</code> consisting of lowercase English letters.</p> <p>You <strong>must</strong> repeatedly perform the following operation while the string <code>s</code> has <strong>at least</strong> two <strong>consecutive </strong>characters:</p> <ul> <li>Remove the <strong>leftmost</strong> pair of <strong>adjacent</strong> characters in the string that are <strong>consecutive</strong> in the alphabet, in either order (e.g., <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>, or <code>&#39;b&#39;</code> and <code>&#39;a&#39;</code>).</li> <li>Shift the remaining characters to the left to fill the gap.</li> </ul> <p>Return the resulting string after no more operations can be performed.</p> <p><strong>Note:</strong> Consider the alphabet as circular, thus <code>&#39;a&#39;</code> and <code>&#39;z&#39;</code> are consecutive.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;c&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;c&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;c&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;adcb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;dc&quot;</code> from the string, leaving <code>&quot;ab&quot;</code> as the remaining string.</li> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;zadb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;db&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;za&quot;</code> from the string, leaving <code>&quot;db&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;db&quot;</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Stack; String; Simulation
C++
class Solution { public: string resultingString(string s) { string stk; for (char c : s) { if (stk.size() && (abs(stk.back() - c) == 1 || abs(stk.back() - c) == 25)) { stk.pop_back(); } else { stk.push_back(c); } } return stk; } };
3,561
Resulting String After Adjacent Removals
Medium
<p>You are given a string <code>s</code> consisting of lowercase English letters.</p> <p>You <strong>must</strong> repeatedly perform the following operation while the string <code>s</code> has <strong>at least</strong> two <strong>consecutive </strong>characters:</p> <ul> <li>Remove the <strong>leftmost</strong> pair of <strong>adjacent</strong> characters in the string that are <strong>consecutive</strong> in the alphabet, in either order (e.g., <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>, or <code>&#39;b&#39;</code> and <code>&#39;a&#39;</code>).</li> <li>Shift the remaining characters to the left to fill the gap.</li> </ul> <p>Return the resulting string after no more operations can be performed.</p> <p><strong>Note:</strong> Consider the alphabet as circular, thus <code>&#39;a&#39;</code> and <code>&#39;z&#39;</code> are consecutive.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;c&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;c&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;c&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;adcb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;dc&quot;</code> from the string, leaving <code>&quot;ab&quot;</code> as the remaining string.</li> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;zadb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;db&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;za&quot;</code> from the string, leaving <code>&quot;db&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;db&quot;</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Stack; String; Simulation
Go
func resultingString(s string) string { isContiguous := func(a, b rune) bool { x := abs(int(a - b)) return x == 1 || x == 25 } stk := []rune{} for _, c := range s { if len(stk) > 0 && isContiguous(stk[len(stk)-1], c) { stk = stk[:len(stk)-1] } else { stk = append(stk, c) } } return string(stk) } func abs(x int) int { if x < 0 { return -x } return x }
3,561
Resulting String After Adjacent Removals
Medium
<p>You are given a string <code>s</code> consisting of lowercase English letters.</p> <p>You <strong>must</strong> repeatedly perform the following operation while the string <code>s</code> has <strong>at least</strong> two <strong>consecutive </strong>characters:</p> <ul> <li>Remove the <strong>leftmost</strong> pair of <strong>adjacent</strong> characters in the string that are <strong>consecutive</strong> in the alphabet, in either order (e.g., <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>, or <code>&#39;b&#39;</code> and <code>&#39;a&#39;</code>).</li> <li>Shift the remaining characters to the left to fill the gap.</li> </ul> <p>Return the resulting string after no more operations can be performed.</p> <p><strong>Note:</strong> Consider the alphabet as circular, thus <code>&#39;a&#39;</code> and <code>&#39;z&#39;</code> are consecutive.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;c&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;c&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;c&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;adcb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;dc&quot;</code> from the string, leaving <code>&quot;ab&quot;</code> as the remaining string.</li> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;zadb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;db&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;za&quot;</code> from the string, leaving <code>&quot;db&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;db&quot;</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Stack; String; Simulation
Java
class Solution { public String resultingString(String s) { StringBuilder stk = new StringBuilder(); for (char c : s.toCharArray()) { if (stk.length() > 0 && isContiguous(stk.charAt(stk.length() - 1), c)) { stk.deleteCharAt(stk.length() - 1); } else { stk.append(c); } } return stk.toString(); } private boolean isContiguous(char a, char b) { int t = Math.abs(a - b); return t == 1 || t == 25; } }
3,561
Resulting String After Adjacent Removals
Medium
<p>You are given a string <code>s</code> consisting of lowercase English letters.</p> <p>You <strong>must</strong> repeatedly perform the following operation while the string <code>s</code> has <strong>at least</strong> two <strong>consecutive </strong>characters:</p> <ul> <li>Remove the <strong>leftmost</strong> pair of <strong>adjacent</strong> characters in the string that are <strong>consecutive</strong> in the alphabet, in either order (e.g., <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>, or <code>&#39;b&#39;</code> and <code>&#39;a&#39;</code>).</li> <li>Shift the remaining characters to the left to fill the gap.</li> </ul> <p>Return the resulting string after no more operations can be performed.</p> <p><strong>Note:</strong> Consider the alphabet as circular, thus <code>&#39;a&#39;</code> and <code>&#39;z&#39;</code> are consecutive.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;c&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;c&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;c&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;adcb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;dc&quot;</code> from the string, leaving <code>&quot;ab&quot;</code> as the remaining string.</li> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;zadb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;db&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;za&quot;</code> from the string, leaving <code>&quot;db&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;db&quot;</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Stack; String; Simulation
Python
class Solution: def resultingString(self, s: str) -> str: stk = [] for c in s: if stk and abs(ord(c) - ord(stk[-1])) in (1, 25): stk.pop() else: stk.append(c) return "".join(stk)
3,561
Resulting String After Adjacent Removals
Medium
<p>You are given a string <code>s</code> consisting of lowercase English letters.</p> <p>You <strong>must</strong> repeatedly perform the following operation while the string <code>s</code> has <strong>at least</strong> two <strong>consecutive </strong>characters:</p> <ul> <li>Remove the <strong>leftmost</strong> pair of <strong>adjacent</strong> characters in the string that are <strong>consecutive</strong> in the alphabet, in either order (e.g., <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code>, or <code>&#39;b&#39;</code> and <code>&#39;a&#39;</code>).</li> <li>Shift the remaining characters to the left to fill the gap.</li> </ul> <p>Return the resulting string after no more operations can be performed.</p> <p><strong>Note:</strong> Consider the alphabet as circular, thus <code>&#39;a&#39;</code> and <code>&#39;z&#39;</code> are consecutive.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abc&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;c&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;c&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;c&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;adcb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;dc&quot;</code> from the string, leaving <code>&quot;ab&quot;</code> as the remaining string.</li> <li>Remove <code>&quot;ab&quot;</code> from the string, leaving <code>&quot;&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;zadb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;db&quot;</span></p> <p><strong>Explanation:</strong></p> <ul> <li>Remove <code>&quot;za&quot;</code> from the string, leaving <code>&quot;db&quot;</code> as the remaining string.</li> <li>No further operations are possible. Thus, the resulting string after all possible removals is <code>&quot;db&quot;</code>.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Stack; String; Simulation
TypeScript
function resultingString(s: string): string { const stk: string[] = []; const isContiguous = (a: string, b: string): boolean => { const x = Math.abs(a.charCodeAt(0) - b.charCodeAt(0)); return x === 1 || x === 25; }; for (const c of s) { if (stk.length && isContiguous(stk.at(-1)!, c)) { stk.pop(); } else { stk.push(c); } } return stk.join(''); }
3,564
Seasonal Sales Analysis
Medium
<p>Table: <code>sales</code></p> <pre> +---------------+---------+ | Column Name | Type | +---------------+---------+ | sale_id | int | | product_id | int | | sale_date | date | | quantity | int | | price | decimal | +---------------+---------+ sale_id is the unique identifier for this table. Each row contains information about a product sale including the product_id, date of sale, quantity sold, and price per unit. </pre> <p>Table: <code>products</code></p> <pre> +---------------+---------+ | Column Name | Type | +---------------+---------+ | product_id | int | | product_name | varchar | | category | varchar | +---------------+---------+ product_id is the unique identifier for this table. Each row contains information about a product including its name and category. </pre> <p>Write a solution to find the most popular product category for each season. The seasons are defined as:</p> <ul> <li><strong>Winter</strong>: December, January, February</li> <li><strong>Spring</strong>: March, April, May</li> <li><strong>Summer</strong>: June, July, August</li> <li><strong>Fall</strong>: September, October, November</li> </ul> <p>The <strong>popularity</strong> of a <strong>category</strong> is determined by the <strong>total quantity sold</strong> in that <strong>season</strong>. If there is a <strong>tie</strong>, select the category with the highest <strong>total revenue</strong> (<code>quantity &times; price</code>).</p> <p>Return <em>the result table ordered by season in <strong>ascending</strong> order</em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>sales table:</p> <pre class="example-io"> +---------+------------+------------+----------+-------+ | sale_id | product_id | sale_date | quantity | price | +---------+------------+------------+----------+-------+ | 1 | 1 | 2023-01-15 | 5 | 10.00 | | 2 | 2 | 2023-01-20 | 4 | 15.00 | | 3 | 3 | 2023-03-10 | 3 | 18.00 | | 4 | 4 | 2023-04-05 | 1 | 20.00 | | 5 | 1 | 2023-05-20 | 2 | 10.00 | | 6 | 2 | 2023-06-12 | 4 | 15.00 | | 7 | 5 | 2023-06-15 | 5 | 12.00 | | 8 | 3 | 2023-07-24 | 2 | 18.00 | | 9 | 4 | 2023-08-01 | 5 | 20.00 | | 10 | 5 | 2023-09-03 | 3 | 12.00 | | 11 | 1 | 2023-09-25 | 6 | 10.00 | | 12 | 2 | 2023-11-10 | 4 | 15.00 | | 13 | 3 | 2023-12-05 | 6 | 18.00 | | 14 | 4 | 2023-12-22 | 3 | 20.00 | | 15 | 5 | 2024-02-14 | 2 | 12.00 | +---------+------------+------------+----------+-------+ </pre> <p>products table:</p> <pre class="example-io"> +------------+-----------------+----------+ | product_id | product_name | category | +------------+-----------------+----------+ | 1 | Warm Jacket | Apparel | | 2 | Designer Jeans | Apparel | | 3 | Cutting Board | Kitchen | | 4 | Smart Speaker | Tech | | 5 | Yoga Mat | Fitness | +------------+-----------------+----------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +---------+----------+----------------+---------------+ | season | category | total_quantity | total_revenue | +---------+----------+----------------+---------------+ | Fall | Apparel | 10 | 120.00 | | Spring | Kitchen | 3 | 54.00 | | Summer | Tech | 5 | 100.00 | | Winter | Apparel | 9 | 110.00 | +---------+----------+----------------+---------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li><strong>Fall (Sep, Oct, Nov):</strong> <ul> <li>Apparel: 10 items sold (6 Jackets in Sep, 4 Jeans in Nov), revenue $120.00 (6&times;$10.00 + 4&times;$15.00)</li> <li>Fitness: 3 Yoga Mats sold in Sep, revenue $36.00</li> <li>Most popular: Apparel with highest total quantity (10)</li> </ul> </li> <li><strong>Spring (Mar, Apr, May):</strong> <ul> <li>Kitchen: 3 Cutting Boards sold in Mar, revenue $54.00</li> <li>Tech: 1 Smart Speaker sold in Apr, revenue $20.00</li> <li>Apparel: 2 Warm Jackets sold in May, revenue $20.00</li> <li>Most popular: Kitchen with highest total quantity (3) and highest revenue ($54.00)</li> </ul> </li> <li><strong>Summer (Jun, Jul, Aug):</strong> <ul> <li>Apparel: 4 Designer Jeans sold in Jun, revenue $60.00</li> <li>Fitness: 5 Yoga Mats sold in Jun, revenue $60.00</li> <li>Kitchen: 2 Cutting Boards sold in Jul, revenue $36.00</li> <li>Tech: 5 Smart Speakers sold in Aug, revenue $100.00</li> <li>Most popular: Tech and Fitness both have 5 items, but Tech has higher revenue ($100.00 vs $60.00)</li> </ul> </li> <li><strong>Winter (Dec, Jan, Feb):</strong> <ul> <li>Apparel: 9 items sold (5 Jackets in Jan, 4 Jeans in Jan), revenue $110.00</li> <li>Kitchen: 6 Cutting Boards sold in Dec, revenue $108.00</li> <li>Tech: 3 Smart Speakers sold in Dec, revenue $60.00</li> <li>Fitness: 2 Yoga Mats sold in Feb, revenue $24.00</li> <li>Most popular: Apparel with highest total quantity (9) and highest revenue ($110.00)</li> </ul> </li> </ul> <p>The result table is ordered by season in ascending order.</p> </div>
Database
Python
import pandas as pd def seasonal_sales_analysis( products: pd.DataFrame, sales: pd.DataFrame ) -> pd.DataFrame: df = sales.merge(products, on="product_id") month_to_season = { 12: "Winter", 1: "Winter", 2: "Winter", 3: "Spring", 4: "Spring", 5: "Spring", 6: "Summer", 7: "Summer", 8: "Summer", 9: "Fall", 10: "Fall", 11: "Fall", } df["season"] = df["sale_date"].dt.month.map(month_to_season) seasonal_sales = df.groupby(["season", "category"], as_index=False).agg( total_quantity=("quantity", "sum"), total_revenue=("quantity", lambda x: (x * df.loc[x.index, "price"]).sum()), ) seasonal_sales["rk"] = ( seasonal_sales.sort_values( ["season", "total_quantity", "total_revenue"], ascending=[True, False, False], ) .groupby("season") .cumcount() + 1 ) result = seasonal_sales[seasonal_sales["rk"] == 1].copy() return result[ ["season", "category", "total_quantity", "total_revenue"] ].sort_values("season")