implementation of polymorphism by using arrays

import java.lang.*;	//syatem library file
import java.lang.reflect.Array;
import java.io.*;	//printstream classes
import java.util.*;	//bcz of scanner class
import java.io.*;

class parasbhatt
{
	void fn() 
	{
		System.out.println("hey paras bhatt");
	}
}

class paras extends parasbhatt
{
	void fn() 
	{
		System.out.println("hey paras");
	}
}

class bhatt extends parasbhatt
{
	void fn() 
	{
		System.out.println("hey bhatt");
	}
}

public class UdemyClasses
{
	public static void main(String args[]) 
	{
//		int array[] = new int[3];
		parasbhatt ref[] = new parasbhatt[3];
		
		for(int i=0;i<ref.length;i++) 
		{
			int option;
			System.out.println("choose your option:");
			
			Scanner take = new Scanner(System.in);
			option = take.nextInt();
			
			switch(option) 
			{
			case 1:
				ref[i] = new parasbhatt(); 
				break;
				
			case 2:
				ref[i] = new paras(); 
				break;
				
			case 3:
				ref[i] = new bhatt(); 
				break;
				
			case 4:
				break;			
			}
			if(option == 4) 
			{
				System.out.println("EXIT");
				break;
			}
			
			ref[i].fn();
			
		}
		
		for(int i=0;i<ref.length;i++) 
		{
			ref[i].fn();
		}
	}
}