n = int(input())
boxes = []
for _ in range(n):
    x, y, z = map(int, input().split())
    dims = sorted([x, y, z])
    boxes.append((dims[0], dims[1], dims[2]))

boxes.sort()

dp = [1] * n
for i in range(n):
    for j in range(i):
        if (boxes[j][0] < boxes[i][0] and
            boxes[j][1] < boxes[i][1] and
            boxes[j][2] < boxes[i][2]):
            dp[i] = max(dp[i], dp[j] + 1)

print(max(dp) if n > 0 else 0)