using System;

using System.Collections;

public class Program

{

    public static void Main()

    {

        Stack s = new Stack();

        s.Push(3);

        s.Push(4);

        s.Push(5);

        s.Push(6);

        Console.WriteLine("No. of Elements :" + s.Count);

        Console.WriteLine(s.Pop());

        Console.WriteLine("No. of Elements :" + s.Count);

        Console.WriteLine(s.Peek());

        Console.WriteLine("No. of Elements :" + s.Count);

        Console.WriteLine(s.Pop());

        Queue q = new Queue();

        q.Enqueue(1);

        q.Enqueue(2);

        q.Enqueue(3);

        q.Enqueue(4);

        Console.WriteLine("\nNo. of Elements :" + q.Count);

        Console.WriteLine(q.Dequeue());

        Console.WriteLine("No. of Elements :" + q.Count);

        Console.WriteLine(q.Peek());

        Console.WriteLine("No. of Elements :" + q.Count);

        Console.WriteLine(q.Dequeue());

    }

}