def cookies(k, A):
    heapq.heapify(A)
    count = 0
    while True:
        c1 = heapq.heappop(A)
        if c1 >= k:
            return count
        if len(A) == 0:
            return -1
        c2 = heapq.heappop(A)
        new_cookie = c1 + 2 * c2
        heapq.heappush(A, new_cookie)
        count += 1
    return count