#include <cstdio>
#include <iostream>
#include <vector>
#include <set>
#include <cmath>
#include <climits>
#include <list>
#include <iomanip>
#include <cstdlib>
#include <fstream>
#include <map>
#include <algorithm>

using namespace std;

int ans = 0, n, m, t[20][20], aux[20][20], p[20];

void bt( int poz) {
    if (poz > n) {
        for (int i = 1; i <= n; i++)
            for (int j = 1; j <= m; j++)
                aux[i][j] = p[i] * t[i][j];
        int total = 0;
        for (int j = 1; j <= m; j++) {
            int s = 0;
            for (int i = 1; i <= n; i++) {
                s += aux[i][j];
            }
            if (s < 0)
                s = -s;
            total += s;
        }
        if (total > ans)
            ans = total;
        return;
    }
    p[poz] = 1;
    bt(poz + 1);
    p[poz] = -1;
    bt(poz + 1);
}

int main() {
    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);

    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n >> m;
    for (int i = 1; i <= n; i++)
        for (int j = 1; j <= m; j++)
            cin >> t[i][j];
    bt(1);
    cout << ans;

    return 0;
}