#include <iostream>
#include <fstream>
using namespace std;
int x[40],n,m,a[20][20],i,j,smax;

void compar(){
    int s,ss,y;
    s=ss=0;

    for(j=1;j<=m;j++){
    ss=0;
    for(i=1;i<=n;i++)
        if(x[i])
        ss=ss-a[i][j];
        else
        ss=ss+a[i][j];
        if(ss<0)s-=ss;
        else s+=ss;
    }
   if (s>smax)smax=s;
}

void abc(int k){
    for(int i=0;i<=1;i++){
        x[k]=i;
        if(k==n)  compar();
        else abc(k+1);
    }
}

int main(){
    freopen("flip.in","r",stdin);
    freopen("flip.out","w",stdout);
    scanf("%d%d",&n,&m);
    for(i=1;i<=n;i++)
        for(j=1;j<=m;j++)
        scanf("%d",&a[i][j]);
    abc(1);
   printf("%d",smax);
    return 0;
}