#include<fstream>
#define mn INT_MIN
using namespace std;
int v[18][18],a[18],n,m,smax=-1000000;
void vrf()
{
	int i,j,s=0,ss=0;
	for (j=1;j<=m;j++)
	{
		s=0;
		for (i=1;i<=n;i++)
			s+=v[i][j]*a[i];
		ss+=abs(s);
	}
	if (ss>smax)
		smax=ss;
}
void bkt(int i)
{
	if (i==n)
		vrf();
	else
	{
	a[i]=-1;
		bkt(i+1);
	a[i]=1;
		bkt(i+1);
	}
}
void citire()
{
	int i,j;
	ifstream in("flip.in");
	in>>n,m;
	for (i=1;i<=n;i++)
		for (j=1;j<=m;j++)
			in>>v[i][j];
	in.close();
}
void afis()
{
	ofstream out("flip.out");
	out<<smax<<'\n';
	out.close();
}
int main()
{
	citire();
	bkt(1);
	afis();
}