#include <fstream>
using namespace std;
int main()
{
    int n, m, i, j, k, K, l, L, x[16][16];
    k = 0;
    K = 0;
    ifstream fin("flip.in");
    fin >> n >> m;
    for ( i = 1; i <= n; i++ )
    {
        for ( j = 1; j <= m; j++ )
        {
            fin >> x[i][j];
            k = x[i][j] + k;
        }
    }
    fin.close();
    for ( L = 0; L <= n; L++ )
    {
        for ( l = 0; l <= m; l++ )
        {
            for ( i = 1; i <= n; i++ )
            {
                for ( j = 1; j <= m; j++ )
                {
                    if ( i == L )
                    {
                         K = ( x[i][j] * -1 ) + K;
                    }
                    else if ( j == l )
                    {
                         K = ( x[i][j] * -1 ) + K;
                    }
                    else
                    {
                        K = x[i][j] + K;
                    }
                }
            }
            if ( K > k )
            {
                 k = K;
            }
            K = 0;
        }
    }
    ofstream fout("flip.out");
    fout << k;
    fout.close();
    return 0;
}