n, x, q = map(int, input().split())
ans = 0
for _ in range(q):
    m = int(input())
    F = list(map(int, input().split()))
    t = 0
    C = set()
    for a in F:
        if a == x:
            t = 2
        else:
            if a in C and t != 2:
                t = 1
            C.add(a)
    ans += t
print(ans / 2)