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 java.util.Scanner;



public class JavaApplication158 {


    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);

        int x = sc.nextInt();
        if(x == 1){System.out.println(-1); return;}
        
        if(x % 2 == 0)
            System.out.println(x +" "+2);
        else
            System.out.println((x-1)+" "+2);
        
         
        
        
        
        
      
    }
}