#include <bits/stdc++.h>
#define Nmax 16
#define Mmax 16

using namespace std;

ifstream fin("flip.in");
ofstream fout("flip.out");
int i, j, N, M;
int a[Nmax][Mmax], maxim = 0, s[Nmax];

void cont() {
    int sl, st = 0, i, j;
    for(i = 1; i <= N; i++) {
        sl = 0;
        for(j = 1; j <= M; j++)
            sl += s[j] * a[i][j];
        if (sl < 0) sl = -sl;
        st += sl;
    }
    maxim = max(st, maxim);
}

void back(int k) {
    if (k > M)
        cont();
    else {
        s[k] = 1;
        back(k+1);
        s[k] = -1;
        back(k+1);
    }
}

int main()
{
    fin >> N >> M;
    for(i = 1; i <= N; i++)
        for(j = 1; j <= M; j++)
            fin >> a[i][j];

    back(1);
    cout << maxim;

    fin.close();
    fout.close();

    return 0;
}