#include <stdio.h>
#define abs(x) x > 0 ? x : -x

int main() {
    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);
    int n, m, i, j, k, a[17][17] = {}, s, ans, sc;
    scanf("%d%d", &n, &m);
    for(i = 1; i <= n; ++i)
        for(j = 1; j <= m; ++j) {
            scanf("%d", &a[i][j]);
            ans += a[i][j];
        }
    for(k = 0; k < 1<<n; ++k) {
        s = 0;
        for(j = 1; j <= m; ++j) {
            sc = 0;
            for(i = 1; i <= n; ++i)
                if(k & (1 << (i-1)))
                    sc -= a[i][j];
                else
                    sc += a[i][j];
            s += abs(sc);
        }
        if(s > ans)
            ans = s;
    }
    printf("%d\n", ans);
}