lc225.用队列实现栈

题目链接：

题解

最简单的模拟，用一个 vector 就可以？好像是偷懒了。。。。

参考代码

/*
 * @lc app=leetcode.cn id=225 lang=cpp
 *
 * [225] 用队列实现栈
 */

// @lc code=start
class MyStack {
    vector<int>q;
public:

    MyStack() {
    }
    
    void push(int x) {
        q.push_back(x);
    }
    
    int pop() {
        int ret = q[q.size()-1];
        q.pop_back();
        return ret;
    }
    
    int top() {
        return q[q.size()-1];
    }
    
    bool empty() {
        if (q.size() == 0) return true;
        return false;
    }
};

/**
 * Your MyStack object will be instantiated and called as such:
 * MyStack* obj = new MyStack();
 * obj->push(x);
 * int param_2 = obj->pop();
 * int param_3 = obj->top();
 * bool param_4 = obj->empty();
 */
// @lc code=end