//
//  main.cpp
//  Alex
//
//  Created by Hurjui Alexandru Mihai on 02/11/2018.
//  Copyright © 2019 Hurjui Alexandru Mihai. All rights reserved.
//

#include <fstream>
using namespace std;

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

int s, smax;
int n, a[16][16], m;

void genl(int k)
{
    if (k == n)
    {
        if (s > smax)
            smax = s;
    }
    else
    {
        int i, s2;
        genl(k+1);
        s2 = s;
        for (i = 0; i<m; i++)
            s = s - 2 * a[k][i];
        genl(k+1);
        s = s2;
    }
}

void genc(int k)
{
    if (k == m)
        genl(0);
    else
    {
        int i, s2;
        genc(k+1);
        s2 = s;
        for (i = 0; i<n; i++)
            s = s - 2*a[i][k];
        genc(k+1);
        s = s2;
    }
}

int main()
{
    int i, j;
    smax = 0;
    fin >> n >> m;
    for (i = 0; i<n; i++)
        for (j = 0; j<m; j++)
        {
            fin >> a[i][j];
            smax = smax + a[i][j];
        }
    s = smax;
    genc(0);
    fout << smax;
    return 0;
}