#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], rows[Nmax], maxsum = 0;

void bkt(int idx = 0) {
    if (idx == n) {
        int sum = 0;
        for (int j = 0; j < m; ++j) {
            int colsum = 0;
            for (int i = 0; i < n; ++i)
                colsum += rows[i] * a[i][j];
            sum += abs(colsum);
        }
        maxsum = max(maxsum, sum);
    }
    else {
        rows[idx] = 1, bkt(idx + 1);
        rows[idx] = -1, bkt(idx + 1);
    }
}

int main()
{
    fin >> n >> m;
    for(i = 0; i < n; i++)
        for(j = 0; j < m; j++)
            fin >> a[i][j];

    bkt(0);
    cout << maxsum;

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

    return 0;
}