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In the third test case, you can perform the following operations: $\mathtt{1}\underline{\mathtt{10}}\mathtt{1}\xrightarrow{r_1=\mathtt{0}} \mathtt{1}\underline{\mathtt{01}} \xrightarrow{r_2=\mathtt{0}} \underline{\mathtt{10}} \xri
You are given a cycle with $n$ vertices numbered from $0$ to $n-1$. For each $0\le i\le n-1$, there is an undirected edge between vertex $i$ and vertex $((i+1)\bmod n)$ with the color $c_i$ ($c_i=\texttt{R}$ or $\texttt{B}$).
Determine whether the following condition holds for every pair of vertices $(i,j)$ ($0\le i<j\le n-1$):
* There exists a palindrome route between vertex $i$ and vertex $j$. Note that the route may not be simple. Formally, there must exist a sequence $p=[p_0,p_1,p_2,\ldots,p_m]$ such that: * $p_0=i$, $p_m=j$; * For each $0\leq x\le m-1$, either $p_{x+1}=(p_x+1)\bmod n$ or $p_{x+1}=(p_{x}-1)\bmod n$; * For each $0\le x\le y\le m-1$ satisfying $x+y=m-1$, the edge between $p_x$ and $p_{x+1}$ has the same color as the edge between $p_y$ and $p_{y+1}$.
Each test contains multiple test cases. The first line contains the number of test cases $t$ ($1 \le t \le 10^5$) — the number of test cases. The description of the test cases follows.
The first line of each test case contains an integer $n$ ($3\leq n\leq10^6$) — the number of vertices in the cycle.
The second line contains a string $c$ of length $n$ ($c_i=\texttt{R}$ or $\texttt{B}$) — the color of each edge.
It is guaranteed that the sum of $n$ over all test cases does not exceed $10^6$.
For each test case, print "YES" (without quotes) if there is a palindrome route between any pair of nodes, and "NO" (without quotes) otherwise.
You can output the answer in any case (upper or lower). For example, the strings "yEs", "yes", "Yes", and "YES" will be recognized as positive responses.
In the first test case, it is easy to show that there is a palindrome route between any two vertices.
In the second test case, for any two vertices, there exists a palindrome route with only red edges.
In the third test case, the cycle is as follows: $0\color{red}{\overset{\texttt{R}}{\longleftrightarrow}}1\color{blue}{\overset{\texttt{B}}{\longleftrightarrow}}2\color{blue}{\overset{\texttt{B}}{\longleftrightarrow}}3\color{red}{\overset{\t
For an arbitrary binary string $t$$^{\text{∗}}$, let $f(t)$ be the number of non-empty subsequences$^{\text{†}}$ of $t$ that contain only $\mathtt{0}$, and let $g(t)$ be the number of non-empty subsequences of $t$ that contain at least one $\mathtt{1}$.
Note that for $f(t)$ and for $g(t)$, each subsequence is counted as many times as it appears in $t$. E.g., $f(\mathtt{000}) = 7, g(\mathtt{100}) = 4$.
We define the oneness of the binary string $t$ to be $|f(t)-g(t)|$, where for an arbitrary integer $z$, $|z|$ represents the absolute value of $z$.
You are given a positive integer $n$. Find a binary string $s$ of length $n$ such that its oneness is as small as possible. If there are multiple strings, you can print any of them.
$^{\text{∗}}$A binary string is a string that only consists of characters $\texttt{0}$ and $\texttt{1}$.
$^{\text{†}}$A sequence $a$ is a subsequence of a sequence $b$ if $a$ can be obtained from $b$ by the deletion of several (possibly, zero or all) elements. For example, subsequences of $\mathtt{1011101}$ are $\mathtt{0}$, $\mathtt{1}$, $\mathtt{11111}$, $\mathtt{0111}$, but not $\mathtt{000}$ nor $\mathtt{11100}$.
The first line contains an integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases.
The only line of each test case contains an integer $n$ ($1 \leq n \leq 2\cdot10^5$) — the length of $s$.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2\cdot10^5$.
For each test case, output $s$ on a new line. If multiple answers exist, output any.
In the first test case, for the example output, $f(t)=1$ because there is one subsequence that contains only $\mathtt{0}$ ($\mathtt{0}$), and $g(t)=0$ because there are no subsequences that contain at least one $1$. The oneness is $|1-0|=1$. The output $\mathtt{1}$ is correct as well because its oneness is $|0-1|=1$.
For the example output of the second test case, $f(t)=1$ because there is one non-empty subsequence that contains only $\mathtt{0}$, and $g(t)=2$ because there are two non-empty subs
Alice and Bob are playing a game. There is a list of $n$ booleans, each of which is either true or false, given as a binary string $^{\text{∗}}$ of length $n$ (where $\texttt{1}$ represents true, and $\texttt{0}$ represents false). Initially, there are no operators between the booleans.
Alice and Bob will take alternate turns placing and or or between the booleans, with Alice going first. Thus, the game will consist of $n-1$ turns since there are $n$ booleans. Alice aims for the final statement to evaluate to true, while Bob aims for it to evaluate to false. Given the list of boolean values, determine whether Alice will win if both players play optimally.
To evaluate the final expression, repeatedly perform the following steps until the statement consists of a single true or false:
* If the statement contains an and operator, choose any one and replace the subexpression surrounding it with its evaluation. * Otherwise, the statement contains an or operator. Choose any one and replace the subexpression surrounding the or with its evaluation.
For example, the expression true or false and false is evaluated as true or (false and false) $=$ true or false $=$ true. It can be shown that the result of any compound statement is unique.
$^{\text{∗}}$A binary string is a string that only consists of characters $\texttt{0}$ and $\texttt{1}$
The first line contains $t$ ($1 \leq t \leq 10^4$) — the number of test cases.
The first line of each test case contains an integer $n$ ($2 \leq n \leq 2 \cdot 10^5$) — the length of the string.
The second line contains a binary string of length $n$, consisting of characters $\texttt{0}$ and $\texttt{1}$ — the list of boolean values.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
For each testcase, output "YES" (without quotes) if Alice wins, and "NO" (without quotes) otherwise.
You can output "YES" and "NO" in any case (for example, strings "yES", "yes" and "Yes" will be recognized as a positive response).
In the first
Suppose we partition the elements of an array $b$ into any number $k$ of non-empty multisets $S_1, S_2, \ldots, S_k$, where $k$ is an arbitrary positive integer. Define the score of $b$ as the maximum value of $\operatorname{MEX}(S_1)$$^{\text{∗}}$$ + \operatorname{MEX}(S_2) + \ldots + \operatorname{MEX}(S_k)$ over all possible partitions of $b$ for any integer $k$.
Envy is given an array $a$ of size $n$. Since he knows that calculating the score of $a$ is too easy for you, he instead asks you to calculate the sum of scores of all $2^n - 1$ non-empty subsequences of $a$.$^{\text{†}}$ Since this answer may be large, please output it modulo $998\,244\,353$.
$^{\text{∗}}$$\operatorname{MEX}$ of a collection of integers $c_1, c_2, \ldots, c_k$ is defined as the smallest non-negative integer $x$ that does not occur in the collection $c$. For example, $\operatorname{MEX}([0,1,2,2]) = 3$ and $\operatorname{MEX}([1,2,2]) = 0$
$^{\text{†}}$A sequence $x$ is a subsequence of a sequence $y$ if $x$ can be obtained from $y$ by deleting several (possibly, zero or all) elements.
The first line contains an integer $t$ ($1 \leq t \leq 10^4$) — the number of test cases.
The first line of each test case contains an integer $n$ ($1 \leq n \leq 2 \cdot 10^5$) — the length of $a$.
The second line of each test case contains $n$ integers $a_1, a_2, \ldots, a_n$ ($0 \leq a_i < n$) — the elements of the array $a$.
It is guaranteed that the sum of $n$ over all test cases does not exceed $2 \cdot 10^5$.
For each test case, output the answer, modulo $998\,244\,353$.
In the first testcase, we must consider seven subsequences:
* $[0]$: The score is $1$. * $[0]$: The score is $1$. * $[1]$: The score is $0$. * $[0,0]$: The score is $2$. * $[0,1]$: The score is $2$. * $[0,1]$: The score is $2$. * $[0,0,1]$: The score is $3$.
The answer for the first testcase is $1+1+2+2+2+3=11$.
In the last testcase, all subsequences have a score of $0$.
This is the hard version of the problem. In this version, $n \leq 10^6$. You can only make hacks if both versions of the problem are solved.
Orangutans are powerful beings—so powerful that they only need $1$ unit of time to destroy every vulnerable planet in the universe!