from collections import Counter
import itertools
import math

def main():
    n, k = map(int, input().split())
    problems = [input().split()[1:] for _ in range(n)]

    ans = 0
    for contest in itertools.permutations(problems, k):
        c = Counter(itertools.chain.from_iterable(contest))
        ans += c.most_common()[0][1] * 2 <= k

    print(ans // math.factorial(k))


if __name__ == "__main__":
    main()