题解 | #JZ31 栈的压入、弹出序列#

//使用辅助栈，模拟入栈 出栈过程，最后栈空返回真否则假
class Solution {
public:
    bool IsPopOrder(vector<int> pushV,vector<int> popV) {
        stack<int> stackV;
        
        for (int p=0, q=0; p<pushV.size(); ++p) {
            if (pushV[p] != popV[q]) {    //不等则依次压入栈
                stackV.push(pushV[p]);
                
            } else {    //相等时为出栈，则尽可能出栈
                ++q;
                while (stackV.size() && stackV.top() == popV[q]) {    //出栈值与栈顶值相同时则还在出栈
                    stackV.pop();
                    ++q;
                }
            }
        }
        
        return stackV.empty();
    }
};