#include <iostream>
#include <fstream>
#include <algorithm>
#include <cmath>
#include <climits>
#include <math.h>

using namespace std;

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

int n, m, maxs;
int matrix[20][20];
int v[20];

void backtraking(int k){
	int s, sf = 0;
	if(k == m + 1){
		for(int i = 1; i <= n; i++){
			s = 0;
			for(int j = 1; j <= m; j++){
					s += matrix[i][j] * v[j];
			}
			if(s < 0)
					s = -s;
			sf += s;
		}
		maxs = max(maxs, sf);
	}else{
		v[k] = 1;
		backtraking(k+1);
		v[k] = -1;
		backtraking(k+1);
	}
}


int main(){
	in >> n >> m;
	for(int i = 1; i <= n; i++){
		for(int j = 1; j <= m; j++){
			in >> matrix[i][j];
		}
	}
	backtraking(1);
	out << maxs << '\n';

}