#include <iostream>
#include <fstream>

using namespace std;


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

int a[17][17];
int col[17];
int n,m;

int suma = -123456789;


void t(){

	int ss = 0;

	for ( int i = 1; i <= n; ++i ) {
		int sl = 0 ;
		for ( int j = 1; j <= m; ++j ) {
			sl += a[i][j] * col[j] ;
		}
		if ( sl <= 0 ){
			ss -= sl ;}
		else {
			ss += sl; }
	}

	if ( suma < ss ) {
		suma = ss;
	}
}




int btk(int niv) {
	if (niv > m)
	{
		t();
	}
	else 
	{
		col[niv] = 1;
		btk(niv +1);
		col[niv] = -1;
		btk(niv +1);
	}
}

int main()
{

	f >> n >> m;

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


	btk(1);

	g << suma;

	f.close();
	g.close();
		
	return 0;
}