#include <cstdio>
#include <algorithm>
#define maxN 19
using namespace std;
int a[maxN][maxN], smaxx, n, m, i, j;
int x[maxN];
void actualizare()
{
    int i, j, s, s1=0;
    for(i = 1; i <= n; i++)
    {
        s = 0;
        for(j = 1; j <= m; j++)
            s += x[j] * a[i][j];
        if(s < 0) s *= -1;
        s1 += s;
    }
    smaxx = max(smaxx, s1);
}
void backtracking(int k)
{
    int i;
    if(k == m+1)
        actualizare();
    else
    {
        x[k] = -1;
        backtracking(k+1);
        x[k] = 1;
        backtracking(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]);
    backtracking(1);
    printf("%d", smaxx);
    return 0;
}