#include<fstream>
using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");
const int Nmax = 17;
int a[Nmax][Nmax],n,m,smax=-(1<<30);
int main(){
    in>>n>>m;
    for(int i=1;i<=n;i++){
        for(int j=1;j<=m;j++){
            in>>a[i][j];
        }
    }
    for(int k=0;k<(1<<m);k++){
        int ss=0;
        for(int i=1;i<=n;i++){
            int s=0;
            for(int j=1;j<=m;j++){
                if(k&(1<<(j-1))) s+=a[i][j];
                else s-=a[i][j];
            }
            if(s<0) ss+=-s;
            else ss+=s;
        }
        if(ss>smax) smax=ss;
    }
    out<<smax;
    return 0;
}