using System;
using System.Collections.Generic;
using System.Text;
using System.Linq;

class Program
{
    public void Proc()
    {
        Reader.IsDebug = false;
        int hakoCount = int.Parse(Reader.ReadLine());
        HakoList = new Hako[hakoCount];
        for (int i = 0; i < hakoCount; i++)
        {
            HakoList[i] = new Hako(Reader.ReadLine().Split(' ').Select(a => int.Parse(a)).ToArray());
        }
        HakoList = HakoList.OrderByDescending(a => a.Tate).ThenByDescending(a => a.Yoko).ThenByDescending(a => a.Takasa).ToArray();
        int ans = GetAns(0, HakoList[0].Tate+1, HakoList[0].Tate+1, HakoList[0].Tate+1);
        Console.WriteLine(ans);

    }

    private int GetAns(int idx, int tate, int yoko, int takasa)
    {
        if (idx >= HakoList.Length)
        {
            return 0;
        }
        if (!dic.ContainsKey(idx))
        {
            dic.Add(idx, new Dictionary<int, Dictionary<int, Dictionary<int, int>>>());
        }
        if (!dic[idx].ContainsKey(tate))
        {
            dic[idx].Add(tate, new Dictionary<int, Dictionary<int, int>>());
        }
        if(!dic[idx][tate].ContainsKey(yoko)) {
            dic[idx][tate].Add(yoko, new Dictionary<int,int>());
        }
        if(dic[idx][tate][yoko].ContainsKey(takasa)) {
            return dic[idx][tate][yoko][takasa];
        }

        int ans = 0;
        int ret = 0;
        if(HakoList[idx].Tate < tate && HakoList[idx].Yoko <yoko && HakoList[idx].Takasa < takasa) {
            ret = this.GetAns(idx+1, HakoList[idx].Tate, HakoList[idx].Yoko, HakoList[idx].Takasa);
            ans = Math.Max(ans, ret + 1);
        }
        ans = Math.Max(ans, GetAns(idx+1, tate, yoko, takasa));
        dic[idx][tate][yoko][takasa] = ans;
        return ans;
    }


    private Dictionary<int, Dictionary<int, Dictionary<int, Dictionary<int, int>>>> dic = new Dictionary<int, Dictionary<int, Dictionary<int, Dictionary<int, int>>>>();
    private Hako[] HakoList;

    private struct Hako
    {
        public int Tate;
        public int Yoko;
        public int Takasa;
        public Hako(int[] inpt)
        {
            int[] tmp = inpt.OrderByDescending(a => a).ToArray();
            this.Tate = tmp[0];
            this.Yoko = tmp[1];
            this.Takasa = tmp[2];
        }
    }
    public class Reader
    {
        public static bool IsDebug = true;
        private static String PlainInput = @"

4
2 2 2
1 1 1
3 3 3
4 1 4




";
        private static System.IO.StringReader Sr = null;
        public static string ReadLine()
        {
            if (IsDebug)
            {
                if (Sr == null)
                {
                    Sr = new System.IO.StringReader(PlainInput.Trim());
                }
                return Sr.ReadLine();
            }
            else
            {
                return Console.ReadLine();
            }
        }
    }
    static void Main()
    {
        Program prg = new Program();
        prg.Proc();
    }
}