def calc_score(box, i):
    global score
    for j in range(i+1, len(box)):
        if box[i][0] < box[j][0] and box[i][1] < box[j][1] and box[i][2] < box[j][2]:
            score[j] = max(score[j], score[i] + 1)
    return

N = int(input())
box = []
for i in range(N):
    tmp = list(map(int, input().split()))
    tmp.sort()
    box.append(tmp)

box.sort(key=lambda x:x[2])

score = [1 for i in range(N)]

for i in range(N):
    if score[i] == 1:
        calc_score(box, i)

print(max(score))