#include <cstdio>
#include <cstdlib>
#include <cmath>
#include <cstring>

#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>

#include <functional>
#include <cassert>

typedef long long ll;
using namespace std;

#define debug(x) cerr << #x << " = " << (x) << endl;


#define mod 1000000007 //1e9+7(prime number)
#define INF 1000000000 //1e9
#define LLINF 2000000000000000000LL //2e18
#define SIZE 100010

/* TopologicalSort */

vector<int> TopologicalSort(vector<vector<int> > G,int n= -1){
  if(n==-1) n=(int)G.size();
  
  int u;
  vector<int> ret,ret2;
  queue<int> que;
  vector<int> indeg(n+1,0);
  
  for(int i=0;i<n;i++){
    for(int j=0;j<G[i].size();j++){
      indeg[G[i][j]]++;
    }
  }
  
  for(int i=0;i<n;i++){
    if(indeg[i]==0){
      que.push(i);
    }
  }
  
  while(!que.empty()){
    u = que.front();
    que.pop();
    
    ret.push_back(u);
    
    for(int i=0;i<G[u].size();i++){
      indeg[G[u][i]]--;
      if(indeg[G[u][i]]==0){
        que.push(G[u][i]);
      }
    }
  }
  
  if(n==(int)ret.size()){
    return ret;
  }else{
    return ret2;
  }
}



int main(){
  int n;
  int x[SIZE][3];

  
  scanf("%d",&n);

  vector<vector<int> > vec(n, vector<int>());

  for(int i=0;i<n;i++){
    scanf("%d%d%d",x[i]+0,x[i]+1,x[i]+2);

    sort(x[i],x[i]+3);
  }

  for(int i=0;i<n;i++){
    for(int j=0;j<n;j++){
      if(i == j) continue;
      
      if(x[i][0] < x[j][0] &&
         x[i][1] < x[j][1] &&
         x[i][2] < x[j][2]){

        cerr << i << " -> " << j << endl;

        vec[i].push_back(j);
      }
    }
  }

  auto res = TopologicalSort(vec);
  
  int dp[SIZE] = {};
  int ans = 1;
  
  for(int i=0;i<res.size();i++){
    for(int j=0;j<vec[res[i]].size();j++){
      dp[vec[res[i]][j]] = max(dp[vec[res[i]][j]], dp[res[i]] + 1);
      ans = max(ans, dp[vec[res[i]][j]] + 1);
    }
  }

  printf("%d\n",ans);
  
  return 0;
}