AcWing 42. 栈的压入、弹出序列（C++）- 栈、模拟

题目链接：https://www.acwing.com/problem/content/description/40/
题目如下：

class Solution {
public:
    bool isPopOrder(vector pushV,vector popV) {
        //两种情况的特判
        if(pushV.size()==0&&popV.size()==0) return true;
        if(pushV.size()!=popV.size()) return false;
        
        stack stk;
        int index=0;
        for(int i=0;i