#include <iostream>
#include <stdio.h>
using namespace std;
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);

}