#include <fstream>

using namespace std;

ifstream fin("flip.in");
ofstream fout("flip.out");

int a[20][20], n, m, maxi;

int main()
{
	fin >> n >> m;
	for (int i = 1; i <= n; ++i)
		for (int j = 1; j <= m; ++j)
			fin >> a[i][j];

	for (int mask = 0; mask < (1 << m); ++mask)
	{
		int s_mat = 0;
		for (int i = 1; i <= n; ++i)
		{
			int s = 0;
			for (int j = 1; j <= m; ++j)
				if (mask & (1 << (j - 1)))
					s -= a[i][j];
				else s += a[i][j];
			if (s < 0) s *= -1;
			s_mat += s;
		}
		if (s_mat > maxi) maxi = s_mat;
	}

	fout << maxi << "\n";
	return 0;
}