text: Minimum steps to convert all top left to bottom right paths in Matrix as palindrome | Set 2 | Java program for the above approach ; Function for counting minimum number of changes ; Distance of elements from ( 0 , 0 ) will is i range [ 0 , n + m - 2 ] ; Store frequencies of [ 0 , 9 ] at distance i ; Initialize frequencies as 0 ; Count frequencies of [ 0 , 9 ] ; Increment frequency of value matrix [ i ] [ j ] at distance i + j ; Find value with max frequency and count total cells at distance i from front end and rear end ; Change all values to the value with max frequency ; Return the answer ; Driver Code ; Given matrix ; Function call
code: import java . util . * ; class GFG { static final int N = 7 ; static int countChanges ( int matrix [ ] [ ] , int n , int m ) { int dist = n + m - 1 ; int [ ] [ ] freq = new int [ dist ] [ 10 ] ; for ( int i = 0 ; i < dist ; i ++ ) { for ( int j = 0 ; j < 10 ; j ++ ) freq [ i ] [ j ] = 0 ; } for ( int i = 0 ; i < n ; i ++ ) { for ( int j = 0 ; j < m ; j ++ ) { freq [ i + j ] [ matrix [ i ] [ j ] ] ++ ; } } int min_changes_sum = 0 ; for ( int i = 0 ; i < dist / 2 ; i ++ ) { int maximum = 0 ; int total_values = 0 ; for ( int j = 0 ; j < 10 ; j ++ ) { maximum = Math . max ( maximum , freq [ i ] [ j ] + freq [ n + m - 2 - i ] [ j ] ) ; total_values += ( freq [ i ] [ j ] + freq [ n + m - 2 - i ] [ j ] ) ; } min_changes_sum += ( total_values - maximum ) ; } return min_changes_sum ; } public static void main ( String [ ] args ) { int mat [ ] [ ] = { { 1 , 2 } , { 3 , 5 } } ; System . out . print ( countChanges ( mat , 2 , 2 ) ) ; } }