#include <fstream>
using namespace std;

ifstream eu("flip.in");
ofstream tu("flip.out");

int n, m;
int a[20][20],v[20];
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;
    eu>>n>>m;
    for(i=1;i<=n;++i)
        for(j=1;j<=m;++j)
            eu>>a[i][j];
    Back(1);
    tu<<maxim;
    return 0;
}