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):
    for j in range(i):
        if box[i][0] > box[j][0] and box[i][1] > box[j][1] and box[i][2] > box[j][2]:
            score[i] = max(score[j] + 1, score[i])

print(max(score))