#include<stdio.h>
#define DIM 17
int n,sol[DIM],m,a[DIM][DIM],max,s,j,i;
void calcul ()
{
 int s=0,j,i;
 for(j=1;j<=m;++j)
     {
      int sc=0;
    for(i=1;i<=n;++i)
  sc+=sol[i]*a[i][j];
	if(sc<0)
      s+=(-sc);
    else
	 s+=sc;
       }
	   if(s>max)
	max=s;
	}
	void back (int k)
	{
      int val;
   if(k==n+1)
       calcul ();
     else
  for(val=-1;val<=1;val+=2)
       {
     sol[k]=val;
   back (k+1);
	}
       }
	int main ()
	{
	   freopen ("flip.in","r",stdin);
											       freopen ("flip.out","w",stdout);
																																				   scanf("%d%d",&n,&m);
																																				       for(i=1;i<=n;++i)
																																					   for(j=1;j<=m;++j)
																																					       {
																																								    scanf("%d",&a[i][j]);
																																											 s+=a[i][j];
																																											     }
																																												 max=s;
																																												     back (1);
																																													 printf("%d",max);
																																													 return 0;
																																													 }