ArrayList in Java von DC

/* package codechef; // don't place package name! */

import java.util.*;
import java.lang.*;
import java.io.*;

/* Name of the class has to be "Main" only if the class is public. */
class Codechef
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc=new Scanner (System.in);
		int n=sc.nextInt();
	
		    ArrayList<Integer> numbers = new ArrayList<>();
		for(int i=0;i<n;i++){
		   numbers.add(sc.nextInt());
		}
		int x=numbers.get(2)-numbers.get(1);
		System.out.println(x);
	System.out.println(numbers.indexOf(6));
	}
}
Deepak jha