import java.io.*;
import java.util.*;

public class Solution {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int numCookies = sc.nextInt();
        int minSweetness = sc.nextInt();
        int count = 0;
        PriorityQueue < Integer> he = new PriorityQueue(numCookies);
        for(int i = 0; i  <  numCookies; i++){
            int sweetness = sc.nextInt();
            he.add(sweetness);
        }
        while(he.peek()  <  minSweetness && he.size() > 1){
            int ne = he.poll() + 2*he.poll();
            he.add(ne);
            count++;
        }
        if(he.peek() >= minSweetness){
            System.out.println(count);
        } else{
            System.out.println(-1);
        }
    }
}

public static int cookies(int k, List<int> A)
    {
        int count = 0;
        var pqueue = new PriorityQueue<int,int>();
    
        foreach(int e in A)
            pqueue.Enqueue(e,e);   
        
        while(pqueue.Count>1) {
            int x = pqueue.Dequeue();
            if(x>=k) {
                return count;
            }
            else {
                
                int y = pqueue.Dequeue();
                int c = x + (2*y);
                pqueue.Enqueue(c,c);
                count++;
            }
        }
        
        if(pqueue.Peek()>=k)
            return count;
        else
            return -1;    
    }

import heapq

def cookies(k, A):
    heapq.heapify(A)
    minVal = heapq.heappop(A)
    if minVal >= k: return 0
    
    heapq.heappush(A, minVal)
    count = 0
    while(len(A) >= 2):
        min1 = heapq.heappop(A)
        min2 = heapq.heappop(A)
        heapq.heappush(A, min1 + min2 * 2)
        count += 1
        minNew = heapq.heappop(A)
        if minNew >= k: return count
        heapq.heappush(A, minNew)
    return -1

int cookies(int k, vector<int> A) {
    priority_queue <int, vector <int>, greater <int>> q; 
    for(int i = 0; i < A.size(); i++){
        q.push(A[i]);
    }
    int step = 0;
    bool check = true;
    while(1){
        int min_s1 = q.top(); //1st smallest element
        q.pop();
        if(q.empty()){
            if(min_s1 < k) check = false;
            break;
        }
        if(min_s1 >= k) break;
        int min_s2 = q.top(); //2nd smallest element
        q.pop();
        int new_s = min_s1 + 2 * min_s2;
        q.push(new_s);
        step++;
    }
    if(!check) step = -1;
    return step;
}