#include <stdio.h>
long n,m,a[16][16],smax;
int main ()
 {
  long i,j,k,s,t;
  freopen("flip.in","r",stdin);
  scanf("%lld %lld",&n,&m);
  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 (smax<s) smax=s;
   }
freopen("flip,out","W",stdout);printf("%lld\n",smax);
}