[CareerCup] 3.5 Implement Queue using Two Stacks 使用两个栈来实现队列

[题目描述] As the title described, you should only use two stacks to implement a queue's actions.The queue should support push(element), pop() and top() where pop is pop the first(a.k.a front) element in the queue.Both pop and top methods should return t

题目 用栈实现队列 正如标题所述,你需要使用两个栈来实现队列的一些操作. 队列应支持push(element),pop() 和 top(),其中pop是弹出队列中的第一个(最前面的)元素. pop和top方法都应该返回第一个元素的值. 样例 比如push(1), pop(), push(2), push(3), top(), pop(),你应该返回1,2和2 挑战 仅使用两个栈来实现它,不使用任何其他数据结构,push,pop 和 top的复杂度都应该是均摊O(1)的 解题 两个栈stack1

As the title described, you should only use two stacks to implement a queue's actions. The queue should support push(element), pop() and top() where pop is pop the first(a.k.a front) element in the queue. Both pop and top methods should return the va

/* how to use two stacks to implement the queue: offer, poll, peek,size, isEmpty offer(3) offer(2) poll() offer(1) peek() offer(6) poll() poll() 3 2 2 1 in (3 2) (1 6) out (2) (3) 6 (1) stack1(in): is the only stack to store new elements when adding

1. stack(先进后出): pop 拿出并返回最后值: peek 返回最后值: push 加入新值在后面并返回此值. 2. queue(先进先出) : poll = remove 拿出并返第一个值: element = peek 返第一个值: add = offer 加入新值在后面并返回true/false. 做此题时, 第一个stack为基础, 第二个stack为媒介来颠倒顺序, 加时从第一个加, 取时从第二个取. public class Queue { private Stack<In

Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front of queue. peek() -- Get the front element. empty() -- Return whether the queue is empty. Notes: You

题目链接:https://leetcode.com/problems/implement-queue-using-stacks/ 题目:Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front of queue. peek() -- Get the fro

题目链接 https://leetcode-cn.com/problems/implement-queue-using-stacks/ 题目描述 使用栈实现队列的下列操作: push(x) -- 将一个元素放入队列的尾部.pop() -- 从队列首部移除元素.peek() -- 返回队列首部的元素.empty() -- 返回队列是否为空. 示例: MyQueue queue = new MyQueue();queue.push(1);queue.push(2); queue.peek(); //

Implement the following operations of a queue using stacks. push(x) -- Push element x to the back of queue. pop() -- Removes the element from in front of queue. peek() -- Get the front element. empty() -- Return whether the queue is empty. Notes: You