#include<bits/stdc++.h>
using namespace std;
#define FOR(i,a,b) for (int i=(a);i<(b);i++)
#define RFOR(i,a,b) for (int i=(b)-1;i>=(a);i--)
#define REP(i,n) for (int i=0;i<(n);i++)
#define RREP(i,n) for (int i=(n)-1;i>=0;i--)
typedef long long LL;
//typedef __int128 LL;
int N;
LL X[1001];
LL Y[1001];
LL Z[1001];
typedef pair<LL,int> P;
vector<P>v;
int dp[1001];

int main(){
	cin>>N;
	REP(i,N){
	    cin>>X[i]>>Y[i]>>Z[i];
	    vector<LL>a;
	    a.push_back(X[i]);
	    a.push_back(Y[i]);
	    a.push_back(Z[i]);
	    sort(a.begin(),a.end());
	    X[i]=a[0];
	    Y[i]=a[1];
	    Z[i]=a[2];
	    v.push_back(P(Z[i],i));
	}
	sort(v.begin(),v.end());
	REP(i,1001){
	    dp[i]=1;
	}
	REP(i,N){
	    for(int j=i+1;j<N;j++){
	        int a=v[i].second;
	        int b=v[j].second;
	        if(X[a]<X[b]&&Y[a]<Y[b]&&Z[a]<Z[b]){
	           dp[j]=max(dp[j],dp[i]+1);
	        }
	    }
	}
	int ans=0;
	REP(i,1001){
	    ans=max(ans,dp[i]);
	}
        cout<<ans<<endl;
	return(0);
}