//0002
#include <cstdio>

long long cit() {
    long long ans = 0;
    char c = getchar();
    bool neg = false;
    while (c < '0' || c > '9') {
        if (c == '-') {
            c = getchar();
            neg = true;
            break;
        }
        c = getchar();
    }
    while (c >= '0' && c <= '9') {
        ans = (ans << 3) + (ans << 1) + (c - '0');
        c = getchar();
    }
    return (neg) ? -ans : ans;
}

void afis(long long n) {
    int l = 0;
    char c[20];
    if (n == 0) {
        putchar('0');
    }
    if (n < 0) {
        putchar('-');
        n = -n;
    }
    while (n > 0) {
        c[l++] = n % 10 + '0';
        n /= 10;
    }
    for (int i = l - 1; i >= 0; i--) {
        putchar(c[i]);
    }
    putchar('\n');
}

int n, m, ans = 0, a[16][16];
bool ng[16];

void backtrack(int poz) {
    if (poz == n) {
        int b[16][16];
        for (int i = 0; i < n; i++) {
            if (ng[i]) {
                for (int j = 0; j < m; j++) {
                    b[i][j] = -a[i][j];
                }
            } else {
                for (int j = 0; j < m; j++) {
                    b[i][j] = a[i][j];
                }
            }
        }
        int ts = 0;
        for (int j = 0; j < m; j++) {
            int s = 0;
            for (int i = 0; i < n; i++) {
                s += b[i][j];
            }
            ts += (s > 0) ? s : -s;
        }
        if (ts > ans) {
            ans = ts;
        }
        return;
    }
    ng[poz] = true;
    backtrack(poz + 1);
    ng[poz] = false;
    backtrack(poz + 1);
}

int main() {
    freopen("flip.in", "r", stdin);
    freopen("flip.out", "w", stdout);

    n = cit();
    m = cit();
    for (int i = 0; i < n; i++) {
        for (int j = 0; j < m; j++) {
            a[i][j] = cit();
        }
    }

    backtrack(0);
    afis(ans);
    return 0;
}