#include <bits/stdc++.h>
using namespace std; 
long long n;
struct BOX
{
	int x, y ,z;
} box[10005];
vector<int> z[10005];
int dep[10005], in[10005], mx;
void dfs(int x, int fa)
{
	if(fa!=-1) dep[x] = max(dep[x], dep[fa]+1);
	for(auto i:z[x])
	{
		if(i != fa) dfs(i, x);
	}
}
int main()
{
	cin >> n;
	for(int  i = 1; i <= n; i++)
	{
		cin >> box[i].x >> box[i].y >> box[i].z;
		int X=min({box[i].x,box[i].y,box[i].z}), Z=max({box[i].x,box[i].y,box[i].z});
		int Y = box[i].x+box[i].y+box[i].z-X-Z;
		box[i].x = X;
		box[i].y = Y;
		box[i].z = Z;
	}
	for(int i = 1; i <= n; i++)
	{
		for(int j = 1; j <= n; j++)
		{
			if(box[i].z > box[j].z && box[i].y > box[j].y && box[i].x > box[j].x)
			{
				z[i].push_back(j);
				in[j]++; 
			}
		}
	}
	for(int i = 1; i <= n; i++)
	{
		if(!in[i])
		{
			z[0].push_back(i);
		}
	}
	dfs(0, -1);
	for(int i = 1; i <= n; i++)
	{
		mx = max(mx, dep[i]);
	}
	cout << mx;
}