#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 1000000000


int main(){
	
	int n,k;
	cin>>n>>k;
	
	vector<int> a(n);
	rep(i,n)cin>>a[i];
	
	vector<bitset<100001>> pre(n+1),suf(n+1);
	pre[0][0] = 1;
	rep(i,n){
		pre[i+1] = pre[i];
		pre[i+1] |= pre[i]<<a[i];
	}
	
	suf[n][k] = 1;
	for(int i=n-1;i>=0;i--){
		suf[i] = suf[i+1];
		suf[i] |= suf[i+1]>>a[i];
	}
	if(pre.back()[k]==0){
		cout<<-1<<endl;
		return 0;
	}
	int ans = 0;
	rep(i,n){
		pre[i] &= suf[i+1];
		if(!pre[i].any()){
			//cout<<i<<endl;
			ans++;
		}
	}
	cout<<ans<<endl;
	
	return 0;
}