#include <bits/stdc++.h>

using namespace std;

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

#define nmax 18
#define minim -9999999

int a[nmax][nmax], best, n, m;

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

    for(int i = 0; i < n; i++){
        for(int j = 0; j < m; j++){
            fin >> a[i][j];
        }
    }


    best = minim;

    for(auto mask = 0; mask < (1 << n); mask++){
        int total = 0;

        for(int j = 0; j < m; j++){
            int colsum = 0;
            for(int i = 0; i < n; i++){
                if(mask >> i & 1){
                    colsum += -a[i][j];
                }
                else
                    colsum += a[i][j];
            }

            total += abs(colsum);

        }

        best = max(total, best);

    }

    fout << best;

    return 0;
}