剑指offer-栈的压入，弹出序列

class Solution {
public:
    bool IsPopOrder(vector<int> pushV,vector<int> popV) {
        int len = pushV.size();
        if(len==0)
            return false;
        int i=1,j=0;
        stack1.push(pushV[0]);
        while(i<=len && j<len){
            if(stack1.top()!=popV[j]){
                stack1.push(pushV[i]);
                i++;
            } 
            else{
                stack1.pop();
                j++;
            }
        }
        if(stack1.empty())
            return true;
        return false;   
    }
private:
    stack<int> stack1;
};