#include <iostream>
#include <fstream>
using namespace std;
#define MAXD 17
ifstream in("flip.in");
ofstream out("flip.out");
int b[MAXD][MAXD],a[MAXD];
int maxsum,s,n,m;
void citire()
{
    in>>n>>m;
    for(int i=1;i<=n;i++)
        for(int j=1;j<=m;j++)
            in>>b[i][j];
    in.close();
}
void letsplay()
{
    int i,j;
    s=0;
    for(i=1;i<=n;i++)
    {
        int provisional_sum=0;
        for(j=1;j<=m;j++)
        {
            provisional_sum+=b[i][j]*a[j];
        }
        s+=max(provisional_sum, -provisional_sum);
    }
    maxsum=max(maxsum, s);

}
void back(int k)
{
    if(k==m+1)
    {
        letsplay();
        return;
    }
    a[k]=-1;
    back(k+1);
    a[k]=1;
    back(k+1);
}
int main()
{
    citire();
    back(1);
    out<<maxsum;
    out.close();
    return 0;
}