#include <bits/stdc++.h>
using namespace std;

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

int a[17][17], n, m, st[17], s, sp, smax;

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

	for (i = 0; i < (1 << n); i++)
	{
		k = 1, p = i;
		while (p != 0)
        {
            st[k++] = p % 2;
			p /= 2;
		}
		s = 0;
		for (j = 1; j <= m; j++)
		{
			sp = 0;
			for (k = 1; k <= n; k++)
				sp += a[k][j] *(1 - 2 * st[k]);
			s += abs(sp);
		}
		smax = max(smax, s);
	}
	fout << smax;
	return 0;
}