0
点赞
收藏
分享

微信扫一扫

面试问题整理若干

m逆光生长 2023-12-28 阅读 33

12.27 225. 用队列实现栈

class MyStack {
    Queue<Integer> queue1;
    Queue<Integer> queue2;
    public MyStack() {
        queue1 = new LinkedList<>();
        queue2 = new LinkedList<>();
    }
    
    public void push(int x) {
        while(queue1.isEmpty()==false){
            queue2.offer(queue1.poll());
        }
        queue1.offer(x);
        while(queue2.isEmpty() == false){
            queue1.offer(queue2.poll());
        }
    }
    
    public int pop() {
        return queue1.poll();
    }
    
    public int top() {
        return queue1.peek();
    }
    
    public boolean empty() {
        return queue1.isEmpty();
    }
}

/**
 * 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();
 * boolean param_4 = obj.empty();
 */
举报

相关推荐

0 条评论