from collections import Counter
from itertools import accumulate
N,K = list(map(int,input().split()))
A = list(map(int,input().split()))

ca = Counter(A)
s = sorted(ca.values(),reverse=True)
S = [0] + list(accumulate(s)) + [10**18]

for i in range(len(S)):
	if(S[i] >= K):
		print(i)
		exit()