#include <stdio.h>
#include <bits/stdc++.h>
#include <atcoder/all>
using namespace atcoder;
using mint = modint998244353;
using namespace std;
#define rep(i,n) for(int i=0;i<(n);i++)
#define Inf 1000000003

vector<vector<bool>> get(vector<int> a,int K){
	int n = a.size();
	vector dp(n+1,vector<bool>(K+1,false));
	dp[0][0] = true;
	rep(i,n){
		rep(j,K+1){
			if(dp[i][j]){
				dp[i+1][j] = true;
				if(j+a[i]<=K)dp[i+1][j+a[i]] = true;
			}
		}
	}
	return dp;
}

int main(){
	
	int N,K;
	cin>>N>>K;
	
	vector<int> a(N);
	rep(i,N){
		cin>>a[i];
	}
	
	auto x = get(a,K);
	reverse(a.begin(),a.end());
	auto y = get(a,K);
	if(x.back().back()==false){
		cout<<-1<<endl;
		return 0;
	}
	int ans = 0;
	rep(i,N){
		bool f = false;
		rep(j,K+1){
			if(x[i][j]==false)continue;
			if(y[N-1-i][K-j]==false)continue;
			f = true;
			break;
		}
		if(!f)ans++;
		
		
	}
	cout<<ans<<endl;
	
	return 0;
}