Problem: Given an integer x, find 2 integers a and b such that: 

  * 1 ≤ a,b ≤ x 
  * b divides a (a is divisible by b). 
  * a ⋅ b>x. 
  * a/b<x. 

Input

The only line contains the integer x (1 ≤ x ≤ 100).

Output

You should output two integers a and b, satisfying the given conditions, separated by a space. If no pair of integers satisfy the conditions above, print "-1" (without quotes).

Examples

Input

10


Output

6 3

Input

1


Output

-1

Solution (in JAVA):

Solution:
import static java.lang.Math.ceil;
import static java.lang.Math.sqrt;
import java.util.Scanner;

/**
 *
 * @author alex
 */
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int EntradaInt = in.nextInt();
        if (EntradaInt==1) {
            System.out.println(-1);
        }else{
            int aux = (int) ceil(sqrt(EntradaInt));
            if (EntradaInt%aux==0 && EntradaInt != 2 ) {
                System.out.println((aux+1)+" "+(aux+1));
            }else{
                System.out.println(aux+" "+aux);
            }
        }
    }
}