#include <fstream>
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");

int n, m, solution, a[17][17], s[17];

void backTracking(int k)
{
	if (k == n + 1) {
		int sum = 0;
		for (int i = 1; i <= m; i++)
            sum += s[i] > 0 ? s[i] : - s[i];
		solution = max(solution, sum);
		return;
	}

	backTracking(k + 1);

	for (int i = 1; i <= m; ++i)
        s[i] -= 2 * a[k][i];

	backTracking(k + 1);

	for (int i = 1; i <= m; ++i)
        s[i] += 2 * a[k][i];
}

int main()
{
	f >> n >> m;
	for (int i = 1; i <= n; i++)
		for (int j = 1; j <= m; j++) {
			f >> a[i][j];
			s[j] += a[i][j];
		}
	backTracking(1);
	g << solution;
    return 0;
}