#include <bits/stdc++.h>
using namespace std;
struct node{
	int x,y,z,ans;
}a[1005],f[1005];
int n;
bool cmp(node a,node b){
	if (a.x==b.x&&a.y==b.y) return a.z<b.z;
	else if (a.x==b.x) return a.y<b.y;
	return a.x<b.x;
}
signed main ()
{
	cin>>n;
	for (int i=1;i<=n;i++){
		scanf("%d%d%d",&a[i].x,&a[i].y,&a[i].z);
		if (a[i].x<a[i].y) swap(a[i].x,a[i].y);
		if (a[i].x<a[i].z) swap(a[i].x,a[i].z);
		if (a[i].y<a[i].z) swap(a[i].y,a[i].z);
	}	
	sort(a+1,a+n+1,cmp);
	f[0]={0,0,0,0};
	for (int i=1;i<=n;i++){
		f[i]=f[i-1];
		for (int j=0;j<=i-1;j++) 
		if (a[i].x>f[j].x&&a[i].y>f[j].y&&a[i].z>f[j].z){
			if (f[j].ans+1>f[i].ans){
				f[i]={a[i].x,a[i].y,a[i].z,f[j].ans+1};
			}
		}
	}	 
	int ans=0;
	for (int i=1;i<=n;i++)
		ans=max(ans,f[i].ans);
	cout<<ans<<endl;
	return 0;
}