#include <cstdio>
#include <algorithm>
#include <cstdlib>

using namespace std;

const int NMAX = 25;

int a[NMAX][NMAX];
int st[NMAX]; /// vector de flipuri
int n , m;
int mx = 0;
int res = 0;
void backtracking(int k)
{
    if(k == n+1)
    {
        mx = 0;
        for(int i = 1 ; i <= m ; i++)
        {
            int sum = 0;
            for(int j = 1 ; j <= n ; j++)
                sum += a[i][j] * st[j];
            mx += abs(sum);
        }
        res = max(res,mx);
        return;
    }
    st[k] = 1;
    backtracking(k+1); ///aici fac flip-urile
    st[k] = -1;
    backtracking(k+1);
}

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