text: preprocess last row Initialize max
code: int maxv = mat [ N - 1 ] [ N - 1 ] ; for ( int j = N - 2 ; j >= 0 ; j -- ) { if ( mat [ N - 1 ] [ j ] > maxv ) maxv = mat [ N - 1 ] [ j ] ; maxArr [ N - 1 ] [ j ] = maxv ; }