import math from itertools import combinations def is_prime(x): if x < 2: return False if x == 2: return True if x % 2 == 0: return False for i in range(3, int(math.isqrt(x)) + 1, 2): if x % i == 0: return False return True n, k = map(int, input().split()) nums = list(map(int, input().split())) ans = 0 for combo in combinations(nums, k): if is_prime(sum(combo)): ans += 1 print(ans)