#include <stdio.h>
#include <fstream.h>
long n,m,a[16][16],smax;
int main ()
 {
  long i,j,k,s,t;
  std::ifstream f ("flip.in);
  f>>n>>m;
  for (i=0;i<n;i++)
   for (j=0;j<m;j++)
    f>>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;
   }
  std::ofstream g ("flip.out");
  g<<smax;
}