#include <bits/stdc++.h>

using namespace std;

ifstream fin("flip.in");
ofstream fout("flip.out");

int v[17][17];
int m, n;

int calcsuma(int x)
{
    int suma = 0;

    for(int i = 1; i <= m; i++)
    {
        int coloana = 0;

        for(int j = 1; j <= n; j++)
        {
            if(x & (1 << (j - 1)))
            {
                coloana += v[i][j];
            }
            else
            {
                coloana -= v[i][j];
            }
        }
        suma += coloana;
    }

    return suma;

}

int main()
{
    
    fin >> n >> m;

    for(int i = 1; i <= n; i++)
    {
        for(int j = 1; j <= m; j++)
        {
            fin >> v[i][j];
        }
    }

    vector <int> v(n + 1);

    int suma = 0;

    for(int i = 0; i <= (1 << n); i++)
    {
        suma = max(suma, calcsuma(i));
    }

    fout << suma;
    return 0;
}