#include <bits/stdc++.h>
using namespace std;
ifstream fin ("flip.in");
ofstream fout ("flip.out");
int n, m, v[20][20], x, ans;
bool semn[20];
int main() {
    fin >> n >> m;
    for (int i = 1; i <= n; i++) {
        for (int j = 1; j <= m; j++) {
            fin >> v[i][j];
        }
    }
    x = (1 << m);
    for (int k = 0; k < x; k++) {
        memset(semn, 0, sizeof(semn));
        for (int i = 0; i < 16; i++) {
            if (k & (1 << i)) semn[i] = true;
        }
        int sum = 0;
        for (int i = 1; i <= n; i++) {
            int s1 = 0, s2 = 0;
            for (int j = 1; j <= m; j++) {
                if (semn[j]) {
                    s1 += v[i][j];
                    s2 -= v[i][j];
                }
                else {
                    s1 -= v[i][j];
                    s2 += v[i][j];
                }
            }
            sum += max(s1, s2);
        }
        ans = max(ans, sum);
    }
    fout << ans;

    return 0;
}