0225-Implement-stack-using-queues.cs

using System;
using System.Collections.Generic;
using System.Text;

namespace Solution._0225.Implement_stack_using_queues
{
    public class _0225_Implement_stack_using_queues
    {
        /**
     * 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();
     */
        public class MyStack
        {
            /** Initialize your data structure here. */
            Queue<int> queue;
            Queue<int> temp;

            public MyStack()
            {
                queue = new Queue<int>();
            }

            /** Push element x onto stack. */
            public void Push(int x)
            {
                queue.Enqueue(x);
            }

            /** Removes the element on top of the stack and returns that element. */
            public int Pop()
            {
                if (Empty()) return -1;

                temp = new Queue<int>();

                while (queue.Count > 1)
                    temp.Enqueue(queue.Dequeue());

                int pop = queue.Dequeue();
                queue = temp;

                return pop;
            }

            /** Get the top element. */
            public int Top()
            {
                if (Empty()) return -1;

                temp = new Queue<int>();

                while (queue.Count > 1)
                    temp.Enqueue(queue.Dequeue());

                int top = queue.Dequeue();
                temp.Enqueue(top);
                queue = temp;

                return top;
            }

            /** Returns whether the stack is empty. */
            public bool Empty()
            {
                return queue.Count == 0;
            }
        }
    }
}