wordpress视频主题汉化seo关键词优化排名外包
思路:当队列入队的时候,将元素入栈(instack),当队列出栈的时候,先判断栈(outstack)是否为空,如果为空,则将栈(instack)的元素全部放入栈(outstack)中,然后取出栈(outstack)顶元素;如果栈(outstack)不为空,则直接取出栈(outstack)顶元素。
class MyQueue {
private: stack<int> instack,outstack;void inout(){while(!instack.empty()){outstack.push(instack.top());instack.pop();}}public:MyQueue() {}void push(int x) {instack.push(x);}int pop() {if(outstack.empty()){inout();}int x = outstack.top();outstack.pop();return x;}int peek() {if(outstack.empty()){inout();}return outstack.top();}bool empty() {return instack.empty() && outstack.empty();}
};/*** Your MyQueue object will be instantiated and called as such:* MyQueue* obj = new MyQueue();* obj->push(x);* int param_2 = obj->pop();* int param_3 = obj->peek();* bool param_4 = obj->empty();*/