#include <cstdio>
#include <math.h>
using namespace std;
FILE *in=fopen ("flip.in", "r");
FILE *out=fopen ("flip.out", "w");
int n,m,v[20][20],max=-999999;
void citire ()
{
    for (int i=1;i<=n;i++)
        for (int j=1;j<=m;j++)
        fscanf (in,"%d",&v[i][j]);
}
void bkt (int p)
{
    int sumt=0;
    if (p==m+1)
    {
        for (int i=1;i<=n;i++)

            {
                int sum1=0;
                for (int j=1;j<p;j++)
                sum1+=v[i][j];
            sumt+=fabs (sum1);
            }
            if (sumt>max)
            max=sumt;
            return;
    }
    bkt (p+1);
    for (int i=1;i<=n;i++)
        v[i][p]=-v[i][p];
    bkt (p+1);
}
int main()
{
    fscanf (in,"%d%d",&n,&m);
    citire();
    bkt (0);
    fprintf (out, "%d",max);
    return 0;
}