栈的压入、弹出序列

class Solution {
public:
	bool IsPopOrder(vector<int> pushV,vector<int> popV) {
		stack<int> s;
        int k = 0;
        for(int i = 0; i < pushV.size(); i++){
            if(pushV[i] != popV[k]){
                s.push(pushV[i]);
            }else{
                k++;
                while(!s.empty() && s.top() == popV[k]){
                    s.pop();
                    k++;
                }
            }
        }
        if(k != popV.size())
            return false;
        return true;
	}
};