#include <stdio.h>
#include <stdlib.h>
FILE *f,*g;
int i,j;
long n,m,max=0;
long d[1],a[20][20],sol[20];
void ok(int k){
 long s1,s2;
 int i,j;
 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 (s1>max) max=s1;
}
void back(int k){
 int i;
 if (k<=n)
  for (i=0;i<=1;i++){
   sol[k]=d[i];
   ok(1);
   back(k+1);
  }
}
int main(){
 f=fopen("flip.in","r");
 g=fopen("flip.out","w");
 fscanf(f,"%ld%ld",&n,&m);
 for (i=1;i<=n;i++)
  for (j=1;j<=m;j++)
   fscanf(f,"%ld",&a[i][j]);
 d[0]=-1;
 d[1]=1;
 back(1);
 fprintf(g,"%ld\n",max);
 fclose(f);
 fclose(g);
 return 0;
}