[leetcode 234]Implement Queue using Stacks
来源:互联网 发布:华夏风云武将数据 编辑:程序博客网 时间:2024/06/06 06:58
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.
- You must use only standard operations of a stack -- which means only
push to top
,peek/pop from top
,size
, andis empty
operations are valid. - Depending on your language, stack may not be supported natively. You may simulate a stack by using a list or deque (double-ended queue), as long as you use only standard operations of a stack.
- You may assume that all operations are valid (for example, no pop or peek operations will be called on an empty queue)。
- 使用两个栈,模拟队列操作
- AC代码
class Queue {public: // Push element x to the back of queue. void push(int x) { s1.push(x); } // Removes the element from in front of queue. void pop(void) { if(s2.empty()) { while(!s1.empty()) { s2.push(s1.top()); s1.pop(); } } s2.pop(); } // Get the front element. int peek(void) { if(s2.empty()) { while(!s1.empty()) { s2.push(s1.top()); s1.pop(); } } return s2.top(); } // Return whether the queue is empty. bool empty(void) { return s1.empty()&&s2.empty(); }private : stack<int> s1; stack<int> s2;};
其他Leetcode题目AC代码:https://github.com/PoughER/leetcode
0 0
- [leetcode 234]Implement Queue using Stacks
- leetcode :Implement Queue using Stacks
- [LeetCode] Implement Queue using Stacks
- LeetCode Implement Queue using Stacks
- LeetCode || Implement Queue using Stacks
- leetcode Implement Queue using Stacks
- Leetcode Implement Queue using Stacks
- [LeetCode]Implement Queue using Stacks
- 【Leetcode】Implement Queue using Stacks
- LeetCode Implement Queue using Stacks
- Leetcode: Implement Queue using Stacks
- [leetcode] Implement Queue using Stacks
- 【leetcode】Implement Queue using Stacks
- [Leetcode]Implement Queue using Stacks
- [leetcode] Implement Queue using Stacks
- LeetCode-Implement Queue using Stacks
- LeetCode Implement Queue using Stacks
- Leetcode: Implement Queue using Stacks
- 两主机互ping的一些例子及其解释
- leetcode 102 —— Binary Tree Level Order Traversal
- 数据分析与数据挖掘类的职位必备技能
- SDUT 2482 二叉排序树
- WCF基础教程(二)——解析iis8和iis8.5+VS2013发布wcf服务问题
- [leetcode 234]Implement Queue using Stacks
- python正则表达式 re (二)compile
- 大数据.......
- mysql存储引擎InnoDB插入数据的过程详解
- HDU 1789 Doing Homework again
- Spark 性能相关参数配置详解-shuffle篇
- 如何new一个二维数组
- poj 1564 Sum It Up 搜索
- POJ3641(Pseudoprime numbers 费马小定理)