#include <iostream>
#include <vector>
#include <cmath>
#include <map>
#include <set>
#include <iomanip>
#include <queue>
#include <algorithm>
#include <numeric>
#include <deque>
#include <complex>
#include <cassert>

using namespace std;
using ll = long long;

int main(){

    int N, K, ans=0;
    cin >> N >> K;
    vector<int> A(N+1);
    for (int i=1; i<=N; i++) cin >> A[i];
    vector<deque<bool>> dp1(N+2, deque<bool>(K+1)), dp2(N+2, deque<bool>(K+1));
    dp1[0][0] = 1;
    dp2[N+1][0] = 1;
    for (int i=1; i<=N; i++){
        for (int j=0; j<=K; j++){
            if (j-A[i]>=0) dp1[i][j] |= dp1[i-1][j-A[i]];
            dp1[i][j] |= dp1[i-1][j];
        }
    }

    for (int i=N; i>=1; i--){
        for (int j=0; j<=K; j++){
            if (j-A[i]>=0) dp2[i][j] |= dp2[i+1][j-A[i]];
            dp2[i][j] |= dp2[i+1][j];
        }
    }

    if (!dp1[N][K]){
        cout << -1 << endl;
        return 0;
    }

    for (int i=1; i<=N; i++){
        bool f=1;
        for (int j=0; j<=K; j++){
            if (dp1[i-1][j] && dp2[i+1][K-j]) f=0;
        }
        if (f) ans++;
    }

    cout << ans << endl;

    return 0;
}