#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;
    if ( n > 16 || m > 16 )
    {
         return 0;
    }
    else
    {
        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;
    }
}