#include<fstream>
using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");
int n, m, a[17][17], i, j, s;
bool sol[17];
void prelucrare()
{
	int i,j,slin,sc=0;
	for(i=1;i<=n;i++)
	{
		slin = 0;
		for(j=1;j<=m;j++)
			if(sol[j])
				slin -= a[i][j];
			else
				slin += a[i][j];
		if(slin < 0) sc -= slin;
		else sc += slin;
	}
	if(sc > s) s = sc;
}
void bkt(int p)
{
	if(p==m+1)
	{
		prelucrare();
		return;
	}
	sol[p]=0;
	bkt(p+1);
	sol[p]=1;
	bkt(p+1);
}

int main()
{
	in>>n>>m;
	for(i=1;i<=n;i++)
		for(j=1;j<=m;j++)
			in>>a[i][j];
	bkt(a[i][j]);
	out<<s;
	return 0;
}