#include <iostream>
#include <fstream>

using namespace std;

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

int short n, m;
int mat[20][20], a[40], maxVal = 0;

void sol()
{
    int fs, ss = 0;
    for(int i = 0; i < m; i++)
    {
        fs = 0;
        for(int j = 0; j < n; j++)
            fs += a[j] * mat[j][i];
        if(fs < 0)
            fs = -fs;

        ss += fs;
    }

    if(ss > maxVal) maxVal = ss;
}

void bktr(int index)
{
    if(index > n) sol();
    else {
        a[index] = 1;
        bktr(index + 1);
        a[index] = -1;
        bktr(index + 1);
    }
}

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

    bktr(1);
    fout << maxVal;

    return 0;
}