#include <iostream>
#include <algorithm>

using namespace std;

int N, M, a[20][20], sign[20], ans;

void solver() 
{
 	int sum = 0;
 	for(int i = 0; i < N; i++)
 	{
 		int nr = 0;
 	 	for(int j = 0; j < M; j++)
			nr += a[i][j] * sign[j];
		sum += max(-nr, nr);		
 	}
 	ans = max(ans, sum);
}

void back(int k) 
{
 	if(k == M) 
 	{
 		solver();
 		return;
 	}
 	sign[k] = 1;
 	back(k + 1);
 	sign[k] = -1;
 	back(k + 1);
}

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

	cin >> N >> M;
	for(int i = 0; i < N; i++)
		for(int j = 0; j < M; j++)
			cin >> a[i][j];
   	back(0);
   	cout << ans << endl;
}