#include<bits/stdc++.h>
#define m(a,b) a=a<(b)?(b):a
using namespace std;
vector<int>G[1000];
class c
{public:
	int x,y,z;
	void in(int a,int b,int c){int s[3]={a,b,c};sort(s,s+3);x=*s,y=s[1],z=s[2];}
	bool operator<(c a){return a.x>x&&a.y>y&&a.z>z;}
};
int t[1000],s,i,n,k,x,y,z;
int f(int v)
{
	if(t[v]<0){t[v]=0;for(int j=0;j<G[v].size();j++)m(t[v],f(G[v][j])+1);}
	return t[v];
}
main()
{
	c a[1000];
	for(cin>>n;i<n;a[i++].in(x,y,z))cin>>x>>y>>z;
	for(sort(a,a+n);i--;)for(k=n;k--;)if(i-k&&a[k]<a[i])G[i].push_back(k);
	for(;i<n;)t[i++]=-1;
	for(;i--;)m(s,f(i)+1);
	cout<<s<<endl;
}