#include <cstdio>
#define N 20
int n,m,max=-1000000000;
int a[N][N];
int v[N];

void sum()
{
	int s=0,aux;
	for (int j=1;j<=m;++j)
	{
		aux=0;
		for (int i=1;i<=n;++i)
			aux+=v[i]*a[i][j];
		if (aux>0)
			s+=aux;
		else
			s-=aux;
	}
	if (s>max)
		max=s;
}

void back(int p)
{
	if (p>n)
	{
		sum();
		return;
	}
	v[p]=1;
	back(p+1);
	v[p]=-1;
	back(p+1);
}

int main()
{
	freopen ("flip.in","r",stdin);
	freopen ("flip.out","w",stdout);
	scanf("%d %d\n",&n,&m);
	for (int i=1;i<=n;++i)
		for (int j=1;j<=m;++j)
			scanf("%d",&a[i][j]);
	back(1);
	printf("%d",max);
	return 0;
}