import java.util.Scanner;
class stack<E>
{
	private final int size;
	private int top;
	private E[] elements;
	public stack()
	{
		this(10);
	}
	public stack(int s)
	{
		size=s>0?s:10;
		top=-1;
		elements=(E[])new Object[size];
	}
	public void push(E x)
	{
		if(top==size-1)
			System.out.println("Overflow");
		elements[++top]=x;
	}
	public E pop()
	{
		if(top==-1)
			System.out.println("Underflow");
		return elements[top--]; 
	}
	public void display()
	{
		if(top==-1)
			System.out.println("Stack is empty");
		else
		{
			for(int i=0;i<top;i++)
				System.out.println(elements[i]);
		}
	}
}
 
public class stacktest
{
	public static void main(String[] args)
	{
		int ch,ch1;
		stack<Double>d_stack;
		d_stack=new stack<Double>(5);
		Scanner input=new Scanner(System.in);
		do
		{
			System.out.println("Menu is as follows:");
			System.out.println("1.Push\n2.Pop\n3.Display\n4.Exit");
			System.out.println("Enter your choice:");
			ch=input.nextInt();
			switch(ch)
			{
				case 1:	System.out.println("Enter element to push:");
						double item=input.nextInt();
						d_stack.push(item);
						break;
				case 2:	double item1=d_stack.pop();
						System.out.println("Popped item:"+item1);
						break;
				case 3:	d_stack.display();
						break;
				default:	break;
			}
		}while(ch!=4);		
	}
}