import sys

def solve():
    N = int(input())
    hako = [sorted([int(i) for i in input().split()]) for j in range(N)]
    hako.sort()
    ans = 1

    l = 0

    while l < N - 1:
        for j in range(l + 1, N):
            for i in range(3):
                if hako[j][i] <= hako[l][i]:
                    break
            else:
                ans += 1
                break

        l = j

    print(ans)

def debug(x, table):
    for name, val in table.items():
        if x is val:
            print('DEBUG:{} -> {}'.format(name, val), file=sys.stderr)
            return None

if __name__ == '__main__':
    solve()