#include <iostream>
#include <fstream>

using namespace std;

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

const int MAXN = 20;

int n, m, ans;

int mat[MAXN][MAXN], sumaLinie[MAXN];

void bkt(int col)
{
	if (col == m + 1)
	{
		int sum = 0;
		for (int i = 1; i <= n; i++)
		{
			sum += max(sumaLinie[i], -sumaLinie[i]);
		}
		ans = max(ans, sum);
		
		return;
	}

	// cu comutare
	for (int i = 1; i <= n; i++)
	{
		sumaLinie[i] += 2 * -mat[i][col];
	}
	bkt(col + 1);

	// fara comutare
	for (int i = 1; i <= n; i++)
	{
		sumaLinie[i] += 2 * mat[i][col];
	}
	bkt(col + 1);
}

int main()
{
	fin >> n >> m;

	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= m; j++)
		{
			fin >> mat[i][j];
			sumaLinie[i] += mat[i][j];
		}
	}

	bkt(1);

	fout << ans;
}