#include <fstream>
using namespace std;

int a[16][16], sol[16], n, m, max_a = -2000000;

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

void citire();
void scriere();

void calculate_max(int k)
{
    int max_t = 0;
    if(k > m)
    {
        for (int y = 0; y < n; y++) {
            int sum  = 0;
            for (int x = 0; x < m; x++)
                sum += a[y][x] * sol[x];
            if (sum < 0)
                sum = -sum;
            max_t += sum;
        }
        if (max_t > max_a)
            max_a = max_t;
    }
    else
    {
        sol[k] = -1;
        calculate_max(k + 1);
        sol[k] = 1;
        calculate_max(k + 1);
    }
}

int main()
{
    citire();
    calculate_max(0);
    scriere();

    return 0;
}

void citire()
{
    in >> n >> m;
    for(int i = 0; i < n; i++)
        for(int j = 0; j < m; j++)
        in >> a[i][j];
    in.close();
}

void scriere()
{
    out << max_a;
    out.close();
}