#include <iostream>
#include <fstream>
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int n, m;
long a[20][20], best, sc[20];
void calcul()
{
    long nr,sum=0;
    for(int i=1;i<=n;i++)
    {
        nr=0;
        for(int j=1;j<=m;j++)
            nr =nr+ a[i][j] * sc[j];

        sum = sum+max(nr,-nr);
    }
    best = max(best,sum);
}
void BK(int k)
{
    if(k==m+1){calcul();return;}
    sc[k]=-1;
    BK(k+1);
    sc[k]=1;
    BK(k+1);
}
int main()
{
    int i,j;
    f>>n>>m;
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
           f>>a[i][j];
    BK(1);
    g<< best;
    return 0;
}