#!/usr/bin/env python
import os
import sys
from io import BytesIO, IOBase
from collections import defaultdict as ddic, Counter
from itertools import groupby
from heapq import *

MOD = 10**9 + 7
# MOD = 998244353
from math import log2


def gprimes(n):
    sieve = [True] * n
    for i in range(3, int(n**0.5) + 1, 2):
        if sieve[i]:
            sieve[i * i :: 2 * i] = [False] * ((n - i * i - 1) // (2 * i) + 1)
    return [2] + [i for i in range(3, n, 2) if sieve[i]]


# primes = gprimes(int(1e5))
# print("P", len(primes))


def solve():
    N, K = rlist()
    A = rlist()
    count = Counter(A)
    vals = sorted(count.values())
    taken = 0
    ans = 0
    while taken < K:
        taken += vals.pop()
        ans += 1
    return ans


def main():
    T = 1
    # T = rint()

    for tc in range(T):
        ans = solve()
        print(ans)
        # print("First" if ans else "Second")
        # print(*ans)
        # print("YES" if ans else "NO")


# region fastio

BUFSIZE = 8192


class FastIO(IOBase):
    newlines = 0

    def __init__(self, file):
        self._file = file
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None

    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()

    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")
rint = lambda: int(input())


def rlist(n=0):
    if n == 0:
        return list(map(int, input().split()))
    return [list(map(int, input().split())) for _ in range(n)]


# endregion

if __name__ == "__main__":
    main()