#include<fstream.h>
#include<math.h>
long max=0;
long a[18][18],n,m,d[1],sol[18];
void solve()
{long i,j;
 long s1,s2;
 s1=0;
 for(j=1;j<=m;j++)
 {s2=0;
  for(i=1;i<=n;i++)
	  s2+=a[i][j]*sol[i];
  s1+=labs(s2);
 }
 if(max<s1)
	 max=s1;
}
void back(long k)
{long i;
 if(k>n)
	solve();
 else
  for(i=0;i<=1;i++)
  {sol[k]=d[i];
   
   back(k+1);
  }
}
int main()
{ifstream fin("flip.in");
 int i,j;
 fin>>n>>m;
 for(i=1;i<=n;i++)
	 for(j=1;j<=m;j++)
		 fin>>a[i][j];
 fin.close();
 ofstream fout("flip.out");
 d[0]=1;
 d[1]=-1;
 back(1);
 fout<<max;
 fout.close();
 return 0;
}