import sys
input = sys.stdin.readline
from bisect import *
from copy import *
 
def compress(lst):
    """
    B: lstを座圧したリスト
    D: indexから元の値を取得する辞書
    """
    B = []
    D = dict()
    vals = deepcopy(lst)
    vals = list(set(vals))
    vals.sort()
    for i in range(len(lst)):
        ind = bisect_left(vals, lst[i])
        B.append(ind)
    for i in range(len(B)):
        D[lst[i]] = B[i]
    return B, D, vals


N = int(input())
H, W, D = [0] * N, [0] * N, [0] * N
for i in range(N):
    H[i], W[i], D[i] = sorted(map(int, input().split()))
    
H, _, _ = compress(H)
W, _, _ = compress(W)
D, _, _ = compress(D)

A = []
for i in range(N):
    A.append((H[i], W[i], D[i]))

A.sort()
dp = [1] * N
def check(a, b):
    flag = 1
    for i in range(3):
        if A[a][i] >= A[b][i]:
            return False
    return True

for i in range(1, N):
    for j in range(i):
        if check(j, i):
            dp[i] = max(dp[i], dp[j] + 1)

print(max(dp))