// Created by PhantomCracker. Copyright(c) PhantomCracker

#include <iostream>
#include <fstream>
using namespace std;

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

int n, m, sol;
int tabla[26][26];
int raspuns[26];

void verificare()
{
	int suma = 0;
	for(int i=1; i<=n; i++)
	{
		int s = 0;
		for(int j=1; j<=m; j++)
		{
			if(raspuns[j]) s = s-tabla[i][j];
			else s = s+tabla[i][j];
		}
		if(s < 0) suma = suma - s;
		else suma = suma + s;
	}
	if(suma > sol) sol = suma;
}

void backtracking(int k)
{
	if(k == m) verificare();
	else 
	{
		for(int i=0; i<=1; i++)
		{
			raspuns[k] = i;
			backtracking(k+1);
		}
	}
}

int main()
{
	f>>n>>m;
	for(int i=1; i<=n; i++)
		for(int j=1; j<=m; j++)
			f>>tabla[i][j];

		backtracking(1);
		//cout<<endl<<"Solutia este "<<sol;
		g<<sol;

	cout<<endl;
	f.close();
	g.close();
	return 0;
}