Find count of occurrences of each prime factor
unordered_map < int , int > mp ; int row_no = 0 ; long long max_factor = 0 ; for ( int i = 0 ; i < N ; i ++ ) { for ( int j = 0 ; j < M ; j ++ ) { int no = arr [ i ] [ j ] ; for ( int k = 0 ; k < prime . size ( ) ; k ++ ) { while ( no > 1 && no % prime [ k ] == 0 ) { no /= prime [ k ] ; mp [ prime [ k ] ] ++ ; } if ( no == 1 ) break ; } }