#include <cstdio>
#include <cstdlib>
#include <cmath>
using namespace std;
long long n,m,smax,a[16][16];
int main()
{
	freopen("flip.in","r",stdin);
	freopen("flip.out","w",stdout);
	scanf("%lld %lld",&n,&m);
	int i,j,k,s,t;
	for(i=0;i<n;i++)
	{
		for(j=0;j<m;j++)
		{
			scanf("%lld",&a[i][j]);
		}
	}
	for(i=0;i<(1<<m);i++)
	{
		s=0;
		for(k=0;k<n;k++)
		{
			for(t=j=0;j<m;j++)
			{
				if(i&(1<<j))t+=-a[k][j];
				else t+=a[k][j];
			}
			s+=t<-t?-t:t;
		}
		if(s>smax)smax=s;
	}
	printf("%lld\n",smax);
	return 0;
}