def getsmallest(stack, queue):
    if len(stack) == 0:
        return queue.popleft()
    elif len(queue) == 0:
        return stack.pop()
    return queue.popleft() if queue[0] < stack[-1] else stack.pop()
    
def cookies(k, startstack):
    startstack.sort(reverse=True)
    createdqueue = deque()
    numops = 0
    while True:
        if (len(startstack) == 0 or startstack[-1] >= k) and (len(createdqueue) == 0 or createdqueue[0] >= k):
            return numops
        if (len(startstack) + len(createdqueue) < 2):
            return -1
            
        numops += 1
        s1 = getsmallest(startstack, createdqueue)
        s2 = getsmallest(startstack, createdqueue)
        createdqueue.append(s1 + 2 * s2)