#include<cstdio>
#include<algorithm>

using namespace std;

int n, m, i, j, a[20][20], summax = 1 << 31, B[20];

void back(int k)
{
    int i, j, s, sf;
    if(k == m + 1)
    {
        sf = 0;
        for(i = 1; i <= n; i++)
        {
            s = 0;
            for(j = 1; j <= m; j++)
                if(B[j]) s -= a[i][j];
                else s += a[i][j];
            if(s < 0) sf -= s;
            else sf += s;
            summax = max(summax, sf);
        }
    }
    else
    {
        for(i = 0; i <= 1; i++)
        {
            B[k] = i;
            back(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]);

    back(1);

    printf("%d\n", summax);

    return 0;
}