#include <fstream>
using namespace std;
int n, m, a[20][20], sum;

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

void calcul()
{
    for(int srun, r = 0; r < (1<<m); ++r)
    {
        srun = 0;

        for(int t, i = 0; i < n; ++i)
        {
            t = 0;
            for(int j = 0; j < m; ++j)
                if(r&(1<<j)) t += a[i][j];
                else t -= a[i][j];
            if(t < -t) t = -t;
            srun += t;
        }

        if(srun > sum)
            sum = srun;
    }
}

void afisare()
{
    ofstream out("flip.out");
    out << sum << '\n';
    out.close();
}

int main()
{
    citire();
    calcul();
    afisare();
    return 0;
}