/*
Things to notice:
1. do not calculate useless values
2. do not use similar names
 
Things to check:
1. submit the correct file
2. time (it is log^2 or log)
3. memory
4. prove your naive thoughts 
5. long long
6. corner case like n=0,1,inf or n=m
7. check if there is a mistake in the ds or other tools you use
8. fileio in some oi-contest

9. module on time 
10. the number of a same divisor in a math problem
11. multi-information and queries for dp and ds problems
*/
#include<bits/stdc++.h>
using namespace std;
#define fi first
#define se second
#define pii pair<int,int>
#define mp make_pair
#define pb push_back
const int mod=998244353;
const int inf=0x3f3f3f3f;
int n,W;
int cnt[13],sum[1<<13],dp[1<<13];
void solve()
{
	cin>>n>>W;
	while(n--)
	{
		int x;
		cin>>x;
		cnt[x-1]++;
	}
	for(int i=0;i<(1<<13);i++) for(int j=0;j<13;j++) if(i&(1<<j)) sum[i]+=cnt[j];
	memset(dp,0x3f,sizeof(dp));
	dp[0]=0;
	for(int i=0;i<(1<<13);i++)
	{
		int S=(1<<13)-1;
		S^=i;
		for(int j=S;j;j=(j-1)&S) if(sum[j]<=W) dp[i|j]=min(dp[i|j],dp[i]+1);
	}
	cout<<dp[(1<<13)-1];
}
signed main()
{
//	ios::sync_with_stdio(0);
//	cin.tie(0);
	int _=1;
//	cin>>_;
	while(_--) solve();
	return 0;
}