#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define rep(i,j,k) for(int i = j;i <= k;++i)
int W,n;
int a[50100];
int cnt[20];
bool f[10010];
int g[10010];
int main(){
	scanf("%d%d",&n,&W);
	rep(i,1,n) scanf("%d",&a[i]) , cnt[a[i]]++;
	rep(s,0,(1<<13)-1) {
		int res = 0;
		rep(i,1,13) if( (s>>(i-1))&1 )
			res += cnt[i];
		f[s] = (res <= W);
	}
	g[0] = 0;
	rep(s,1,(1<<13)-1) {
		g[s] = 10000000;
		int rs = s;
		while(rs > 0) {
			if( f[rs] ) g[s] = min( g[s] , g[ s - rs ] + 1 );
			rs = (rs-1)&s;
		}
	}
	printf("%d\n",g[(1<<13)-1]);
	return 0;
}