#include <atcoder/all>
using namespace atcoder;
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(v) v.begin(),v.end()
#define inc(x,l,r) ((l)<=(x)&&(x)<(r)) 
#define Unique(x) sort(all(x)), x.erase(unique(all(x)), x.end())
typedef long long ll;
#define int ll
using ld = long double;
using vi = vector<int>;
using vs = vector<string>;
using P = pair<int,int>;
using vp = vector<P>;
template<typename T> using priority_queue_greater = priority_queue<T, vector<T>, greater<T>>;
template<typename T> ostream &operator<<(ostream &os,const vector<T> &v){rep(i,v.size())os<<v[i]<<(i+1!=v.size()?" ":"");return os;}
template<typename T> istream &operator>>(istream& is,vector<T> &v){for(T &in:v)is>>in;return is;}
template<class... T> void in(T&... a){(cin>> ... >> a);}
template<class T> void out(T& a){cout <<a<< '\n';}
template<class T,class... Ts> void out(const T&a, const Ts&... b){cout<< a;(cout<<...<<(cout<<' ',b));cout<<'\n';}
#define INT(...) int __VA_ARGS__; in(__VA_ARGS__)
#define STR(...) string __VA_ARGS__; in(__VA_ARGS__)
#define pcnt __builtin_popcount
int ceil(int x,int y){return x/y+!!(x%y);}
bool ins(string s,string t){return s.find(t)!=string::npos;}
P operator+ (const P &p, const P &q){ return P{p.first+q.first,p.second+q.second};}
P operator- (const P &p, const P &q){ return P{p.first-q.first,p.second-q.second};}
ostream &operator<< (ostream &os, const P &p){os << p.first <<" "<<p.second;return os;}
ostream &operator<< (ostream &os, const modint1000000007 &m){os << m.val();return os;}
ostream &operator<< (ostream &os, const modint998244353 &m){os << m.val();return os;}
template<typename T> bool chmax(T &a, const T b) {if (a < b) {a = b; return true;} else return false; }
template<typename T> bool chmin(T &a, const T b) {if (a > b) {a = b; return true;} else return false; }
void yesno(bool ok){ cout<<(ok?"Yes":"No")<<endl;}
vector<P> dxdy{{1,0},{0,1},{-1,0},{0,-1}};
const int INF = 1e18;
//using mint = modint1000000007;
//using mint = modint998244353;

int dp[10010][1010];
signed main() {
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    cout << fixed << setprecision(20);

    int n,k;cin>>n>>k;
    vi a(n);cin>>a;
    sort(all(a));
    dp[0][0]=1;
    rep(i,n)rep(j,k+1){
        dp[i+1][j]+=dp[i][j];
        if(j+a[i]<=k)dp[i+1][j+a[i]]+=dp[i][j];

    }
    if(dp[n][k]==0){
        cout<<-1<<endl;return 0;
    }

    int ans = 0;
    int t = k;
    for(int i=n;i>0;i--){
        if(dp[i-1][t])break;
        if(dp[i][t]==dp[i-1][t-a[i]]){
            ans++;
        }
        t-=a[i];
        // cout<<t<<endl;
    }


    // rep(j,k+1)cout<<j<<" ";cout<<endl;

    // rep(i,n+1)rep(j,k+1)cout<<dp[i][j]<<" \n"[j==k];

    cout<<ans<<endl;
    
    return 0;
}