#include <cstdio>

using namespace std;

int n, m, a[20][20], sol;
bool v[20];

void bkt(int k)
{
    if(k == n + 1)
    {
        int s = 0, sCol;
        for(int j = 1; j <= m; ++j)
        {
            sCol = 0;
            for(int i = 1; i <= n; ++i)
            {
                if(v[i] == 1) sCol += a[i][j];
                else sCol += (a[i][j] * -1);
            }
            if(sCol < 0) sCol *= -1;
            s += sCol;
        }
        if(s > sol) sol = s;
    }
    else
        for(int i = 0; i <= 1; ++i)
        {
            v[k] = i;
            bkt(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]);
    fclose(stdin);
    bkt(1);
    printf("%d", sol);
    return 0;
}