# import pypyjit;pypyjit.set_param("max_unroll_recursion=-1")
# from bisect import *
from collections import *

# from heapq import *
# from itertools import *
# from math import *
# from datetime import *
# from decimal import*
# from string import ascii_lowercase,ascii_uppercase
# import numpy as np
import sys
import os

# sys.setrecursionlimit(10**6)
INF = 10**18
MOD = 998244353
# MOD = 10**9 + 7
File = open("input.txt", "r") if os.path.exists("input.txt") else sys.stdin


def input():
    return File.readline()[:-1]


# ///////////////////////////////////////////////////////////////////////////


N, K = map(int, input().split())
A = list(map(int, input().split()))
cnt = Counter(A)
cnt = sorted(cnt.values(), reverse=True)
total = 0
for i in range(N):
    total += cnt[i]
    if total >= K:
        print(i + 1)
        break