import java.util.Scanner;
import java.util.PriorityQueue;
public class Solution{
    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        int n = sc.nextInt(), k = sc.nextInt(), c= 0;
        PriorityQueue<Integer> p = new PriorityQueue<>();
        while (n-- > 0) p.add(sc.nextInt());
        while (p.size() >= 2 && p.peek() < k) {
            int min1 = p.remove(), min2 = p.remove();
            p.add(min1 + 2*min2);
            c++;
        }
        System.out.println((p.size() <= 1 && p.peek() < k) ? -1 : c);
        sc.close();
    }
}