#include <fstream>
using namespace std;
 

 
ifstream fin("flip.in");
ofstream fout("flip.out");
 
int n, m;
int a[17][17];
int v[17];
int maxim = -1<<3;
 

 

 
void Back( int k )
{
    long long s,aux=0;
	int i,j;
    if(k==n+1)
    {
        s=0;
        for(i=1;i<=m;++i)
        {
            aux=0;
            for(j=1;j<=n;++j)
                aux=aux+a[j][i]*v[j];
            if(aux<0)
                s=s-aux;
            else
                s=s+aux;
        }
        if(maxim<s)
            maxim=s;
        return;
    }
    v[k]=1;
    Back(k+1);
    v[k]=-1;
    Back(k+1);
}


int main()
{
	int i,j;
    fin>>n>>m;
    for(i=1;i<=n;++i)
        for(j=1;j<=m;++j)
            fin>>a[i][j];
    Back(1);
    fout<<maxim;
    return 0;
}