#include <fstream>
#include <stdlib.h>

using namespace std;

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

int n,m,a[20][20],sol,v[20],s;

void back(int);
int suma();

int main()
{
    f>>n>>m;
    for (int i=1;i<=n;i++)
        for (int j=1;j<=m;j++)
            f>>a[i][j];
    back(1);
    g<<sol<<'\n';
    f.close();g.close();
    return 0;
}

void back(int l)
{
    if (l==n+1)
    {
        int s=suma();
        if (s>sol) sol=s;
    }
    else
    {
        v[l]=1;
        back(l+1);
        v[l]=-1;
        back(l+1);
    }
}

int suma()
{
    int sum=0;
    for (int j=1;j<=m;j++)
    {
        int aux=0;
        for (int i=1;i<=n;i++) aux+=v[i]*a[i][j];
        sum+=abs(aux);
    }
    return sum;
}