#include<stdlib.h>
#include<stdio.h>
int n,m,a[21][21],b[21][21],v[21],SM;
void comutare(int l)
   {
    if(l==m+1)
      {int i,j,s=0,s1,s2;
       for(i=1;i<=m;++i)
	   for(j=1;j<=n;++j) b[j][i]=a[j][i]*v[i];
       for(i=1;i<=n;++i)
	  {s1=s2=0;
	   for(j=1;j<=m;++j) s1+=b[i][j],s2+=b[i][j]*-1;
	   s+=s1>s2?s1:s2;
	   }
       if(s>SM) SM=s;
      }else {
	      v[l]=1;
	      comutare(l+1);
	      v[l]=-1;
	      comutare(l+1);
	     }
   }
int main()
 {
 freopen("flip.in","rt",stdin);
 freopen("flip.out","wt",stdout);
 scanf("%d %d",&n,&m);
 for(int i=1;i<=n;++i)
 for(int j=1;j<=m;++j) scanf("%d",&a[i][j]);
 comutare(1);
 printf("%d\n",SM);
 return 0;
  }