入栈时,首先利用队列的add方法,然后利用循环,把队列里的元素poll出来再add进去,此循环只执行队列的size-1次,执行size次会还原。 classMyStack3{ Queue<Integer> queue = null;/** Initialize your data structure here. */publicMyStack3(){ queue =newLinkedList<Integer>(); }/** Push element x onto s...
## LeetCode 232classMyQueue:def__init__(self):self.l1=[]## queue1 = l1self.l2=[]## queue2 = l2defpush(self,x:int)->None:## Push x onto stackself.l1.append(x)## The right of the list = the top of the stack = the back of the queuedefpop(self)->int:## pop 抽取## ...
}/** Removes the element on top of the stack and returns that element. */publicintpop(){if(q1.isEmpty()) {thrownewNoSuchElementException("[ERROR] The stack is empty!"); }returnq1.remove(); }/** Get the top element. */publicinttop(){if(q1.isEmpty()) {thrownewNoSuchElementExcept...
pop() -- Removes the element on top of the stack. top() -- Get the top element. empty() -- Return whether the stack is empty. Example: MyStack stack = new MyStack(); stack.push(1); stack.push(2); stack.top(); // returns 2 stack.pop(); // returns 2 stack.empty(); //...
仅使用两个队列(queue)实现一个后进先出(last-in-frist-out)(LIFO)的栈(stack)。你实现的栈需要满足常规栈的操作。(push、top、pop、empty)。 implement the MyStack class: void push(int x) Pushes element x to the top of the stack. int pop() Removes the element on the top of the stack and...
题目链接:https://leetcode.com/problems/implement-stack-using-queues/题目: Implement the following operations of a stack using queues. push(x) -- Push element x onto stack. pop() -- Removes the element on top of the stack. top() -- Get the top element. ...
LeetCode 225 Implement Stack using Queues 用队列实现栈,1、两个队列实现,始终保持一个队列为空即可2、一个队列实现栈
LeetCode 225. Implement Stack using Queues 简介:使用队列实现栈的下列操作:push(x) -- 元素 x 入栈;pop() -- 移除栈顶元素;top() -- 获取栈顶元素;empty() -- 返回栈是否为空 Description Implement the following operations of a stack using queues....
https://leetcode-cn.com/problems/implement-stack-using-queues/ 思路 首先演示push()操作; 将元素依次进入队1,进入时用top元素保存当前进入的元素; 如下图: push操作的演示 然后演示pop()操作; 先将除队1中的最后一个元素出队并进入队2,入队2时用top存储入队元素; 再将队列1和队列2进行互换即可。 如下...
leetcode225 implement stack using queues 题目要求 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....