#include<stdio.h>

int b[1001],n,m,a[17][17],max;

void citire()
{ int i,j;
 scanf("%d %d",&n,&m);
 for(i=1;i<=n;i++)
   for(j=1;j<=m;j++)
     {scanf("%d",&a[i][j]);
      max=max+a[i][j];
      }
}

void rezolvare()
{
  int s=0,k,j,x;
  for (j=1; j<=m; j++)
    {x=0;
     for (k=1; k<=n; k++)
     x=x+b[k]*a[k][j];
     if (x<0)
	s=s-x;
      else
	s=s+x;
      }
  if (s>max)
     max=s;

}

void afisare()
{
 printf("%d",max);
}
void back(int k)
{   int l;
    if(k==n+1)
	rezolvare();
     else
       for(l=-1;l<=1;l+=2)
       {
	b[k]=l;
	back(k+1);
    }
}


int main()
{
  freopen("flip.in","r",stdin);
  freopen("flip.out","w",stdout);
  citire();
  back(1);
  afisare();
}