using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        Queue<int> queue = new Queue<int>();

        //Adding elements in the queue

        queue.Enqueue(1);

        queue.Enqueue(4);

        queue.Enqueue(8);

        queue.Enqueue(12);

        //Peek - We can access the first item of the queue

        Console.WriteLine("Peek()- " + queue.Peek());

        //Remove an element from the queue

        //This removes First item from the queue

        //Dequeue returns the removed item from the queue

        int removedItem = queue.Dequeue();

        Console.WriteLine("Dequeue()- "+ removedItem);

        Console.WriteLine("Dequeue()- "+ queue.Dequeue());

        //Next item to be removed

        Console.WriteLine("Peek()- " + queue.Peek());

        //Iterate through the queue, we will use while loop

        //C# has a built-in method TryDequeue(), which will try to dequeue an item

        //If the item can be dequeued, it will dequeue the item and return True

        //If the item can't be dequeued, it will return false , which means Queue is empty

        int current; //current item to be tried by TryDequeue ; to save the dequeued item

        while(queue.TryDequeue(out current))

        {

            Console.WriteLine(current);

        }

    }

}