"""

"""

import sys
from sys import stdin

N,K = map(int,stdin.readline().split())

A = list(map(int,stdin.readline().split()))

dic = {}

for i in A:
    if i not in dic:
        dic[i] = 0
    dic[i] += 1

B = [dic[i] for i in dic]

B.sort()
B.reverse()

s = 0
for i in range(len(B)):

    s += B[i]
    if s >= K:
        print (i+1)
        break