#include <stdio.h>
long n,m,a[16][16],smax;
int main(){
long i,j,k,s,t;
freopen("flip.in","r",stdin);
scanf("%lld %lld",&n,&m);
for(i=0;i<n;i++)
 for(j=0;j<m;j++) scanf("%lld",a[i]+j);
for(i=0;i<(1<<m);i++){
s=0;
for(k=0;k<n;k++){
 for(t=j=0;j<m;j++)
  if(i&(1<<j)) t+=-a[k][j]; else t+=a[k][j];
 s+=t<-t ? -t : t;
}
if(smax<s) smax=s;
}
freopen("flip.out","w",stdout); printf("%lld\n",smax);
return 0;
}