#include <fstream>
using namespace std;

int v[70000], a[16][16], b[16];
int main()
{
	int i, n, max=0, f, s1, s, aux1, aux, p=1, j, m, q;
	ifstream fin("flip.in");
	ofstream fout("flip.out");
	
	fin>>n >>m;
	
	for(i=1;i<=n;++i)
		for(j=1;j<=m;++j)
			fin>>a[i][j];
		aux=n;
		while(aux>0)
			{
				p*=2;
				--aux;
			}
	
	for(i=0;i<=p-1;++i)
	{
		aux=i;
		aux1=n;
		while(aux>0)
		{
			v[aux1]=aux%2;
			aux/=2;
			--aux1;
		}
		s1=0;
		
		for(j=1;j<=n;++j)
		{
			s=0;
			for(q=1;q<=m;++q)
			{
				if(v[q]==0)
					s=s-a[j][q];
				else
					s+=a[j][q];
			}
			s1+=abs(s);
		}
		
		if(s1>max)
			max=s1;
	}
	fout<<max;
	return 0;
}