#include <cstdio>
#include <algorithm>

using namespace std;

int s,retine;
int n,m,st[35],mx;
int a[17][17],alt[17][17];

void verificare(){
    int suma_flip = 0;
    for(int i = 1; i <= n; i++){

        int sum = 0;
        for(int j = 1; j <= m; j++){
            if(st[j] == 1){
                sum -= a[i][j];
            }else
                sum += a[i][j];
        }
        if(sum < 0)
            sum *= -1;
        suma_flip += sum;
        mx = max(suma_flip,mx);
    }
}
void back(int k){
    for(int i = 0; i <= 1; i++){
        st[k] = i;

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