#include <fstream>
#include <vector>
using namespace std;
ifstream cin("flip.in");
ofstream cout("flip.out");
int n, m, sMax, s;
vector<vector<int>>V(18,vector<int>(18,0));
vector<int>Combinari(18);
void verificare() {
	int sTemp,coef,i,j;
	s = 0;
	for (i = 0; i < n; i++) {
		sTemp = 0;
		for (j = 0; j < m; j++) {
			if (Combinari[j] == 1) coef = -1;
			else coef = 1;
			sTemp += V[i][j] * coef;
		}
		if (sTemp < 0)sTemp = -sTemp;
		s += sTemp;
	}
	if (s > sMax)sMax = s;
}
int main()
{
	int i, j;
	cin >> n >> m;
	for (i = 0; i < n; i++) {
		for (j = 0; j < m; j++) {
			cin >> V[i][j];
			sMax += V[i][j];
		}
	}
	i = 0;
	while (i < m) {
		i = 0;
		while (Combinari[i] == 1) {
			Combinari[i] = 0;
			i++;
		}
		if (i >= m) break;
		Combinari[i] = 1;
		//for (j = 0; j < m;j++)cout << Combinari[j] << ' ';
		//cout << '\n';
		verificare();
	}
	cout << sMax;
	/*
		comb pe fiecare col
		sume pe linii  roteste linia dc negativa adauga la suma finala

	*/
}