#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;


long long n, m, smax, a[16][16];


int main()
{
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
    scanf("%lld %lld", &n, &m);
    int i, j, k, s, t;
    for(i=0; i<n; ++i)
    {
             for(j=0; j<m; ++j)
             {
                      scanf("%lld", &a[i][j]);
             }
    }
    for(i=0; i<(1<<m); ++i)
    {
             s = 0;
             for(k=0; k<n; ++k)
             {
                      for(t=j=0; j<m; ++j)
                      {
                                 if( i & (1<<j) ) t+= -a[k][j];
                                 else t+= a[k][j];
                      }
                      s+=t<-t ?-t : t;
             }
             if(s > smax) smax = s;
    }
    printf("%lld\n", smax);
    return 0;
}