#include <fstream>
#include <algorithm>
using namespace std;

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

const int MAXN = 25;
int n, m;
int v[MAXN][MAXN];

int main() {

    fin >> n >> m;
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= m; ++j) {
            fin >> v[i][j];
        }
    }

    int sol = 0;
    int l = (1 << m);
    for (int i = 0; i < l; ++i) {
        int s = 0;
        for (int j = 1; j <= n; ++j) {
            int p = 0;
            for (int k = 1; k <= m; ++k) {
                if (i & (1 << (k - 1))) {
                    p += (v[j][k] * (-1));
                }
                else {
                    p += v[j][k];
                }
            }
            if (p < 0) {
                p = p * (-1);
            }
            s += p;
        }
        sol = max(sol, s);
    }
    fout << sol;

    fout.close();
    return 0;
}