#include <fstream>
#include <iostream>
using namespace std;
int a[17][17], m, n, sl[17], x[17], MAX = -1000001, s;
void verif ()
{
    s = 0;
    for (int i = 0; i < m; ++i)
        sl[i] = 0;
    for (int i = 0; i < m; ++i)
        for (int j = 0; j < n; ++j)
            sl[i] += x[j] * a[i][j];
    for (int i = 0; i < m; ++i)
        {if(sl[i]>0) s+=sl[i];
        else s+=-sl[i];}
    if(s>MAX) MAX=s;
}

void Bktrk (int k)
{
    for (int i = 0; i < 2; i++)
    {
        x[k] =  i * 2-1;
        if (k == n - 1)
            verif ();
        else
            Bktrk (k + 1);
    }
}

int main ()
{
    ifstream f ("flip.in");
    f >> m >> n;
    for (int i = 0; i < m; i++)
        for (int j = 0; j < n; j++)
            f >> a[i][j];
    f.close ();
    Bktrk (0);
    ofstream g ("flip.out");
    g << MAX;
    g.close();
    return 0;
}