#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <iostream>
#include <string>
#include <set>
#include <map>
#include <vector>
#include <queue>
#define ll long long
#define db double
using namespace std;
const ll N = 1e5 + 100;
ll tt,cnt[N],n,k;
void solve() {
	memset(cnt,0,sizeof(cnt));
	scanf("%lld%lld",&n,&k);
	for (ll i = 1;i <= n;i++) {
		ll x;
		scanf("%lld",&x);
		cnt[x]++;
	}
	sort(cnt + 1,cnt + n + 1);
	ll ans = 0;
	for(ll i = n;i >= 1;i--) {
		k -= cnt[i];
		ans++;
		if (k <= 0) {
			break;
		}
	}
	printf("%lld",ans);
}
int main() {
	tt = 1;
	while(tt) {
		solve();
		tt--;
	}
	return 0;
}