from collections import Counter
import sys


def main():
    sys.setrecursionlimit(1000000)
    input = lambda: sys.stdin.readline()[:-1]
    N, K = map(int, input().split())
    A = map(int, input().split())

    cnt = Counter(A).most_common()
    ans = 0
    for _, n in cnt:
        ans += 1
        K -= n
        if K <= 0:
            break
    print(ans)


if not __debug__:
    f = open(sys.argv[1], "r")
    sys.stdin = f

main()