#include <fstream>

using namespace std;

ifstream cin("flip.in");
ofstream cout("flip.out");

int n, m, v[16][16];

int dah(int val) {
    int ans(0);
    for (int i = 0; i < n; ++i) {
        int sum(0);
        for (int j = 0; j < m; ++j) {
            if (val&(1<<j - 1)) {
                sum -= v[i][j];
            }
            else {
                sum += v[i][j];
            }
        }
        ans += max(sum, -sum);
    }
    return ans;
}

int main()
{
    cin >> n >> m;
    for (int i = 0; i < n; ++i) {
        for (int j = 0; j < m; ++j) {
            cin >> v[i][j];
        }
    }
    int sol(0);
    for (int i = 0; i < (1<<m); ++i) {
        sol = max(sol, dah(i));
    }
    cout << sol;
    return 0;
}