#include<bits/stdc++.h>
using namespace std;
const int N=1e5+10;
int a[N];
int n,k,ans,x;
int main(){
	scanf("%d%d",&n,&k);
	for (int i=1;i<=n;i++){
		scanf("%d",&x); a[x]++;
	}
	sort(a+1,a+n+1);
	for (int i=n;i>=1;i--) if (k>a[i]){
		k-=a[i]; ans++;
	}else{
		ans++; break;
	}
	printf("%d\n",ans);
}