题目链接

https://leetcode.cn/problems/implement-stack-using-queues/description/

代码

class MyStack {
public:queue<int> q1;queue<int> q2;MyStack() {}void push(int x) {q1.push(x);}int pop() {int size = q1.size() - 1;while(size--){q2.push(q1.front());q1.pop();}int result = q1.front();q1.pop();q1 = q2;while(!q2.empty()) q2.pop();return result;}int top() {return q1.back();}bool empty() {return q1.empty();}
};/*** 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();*/