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 EhabAndAnotherConstructionProblem {

    public static void main(String[] args) {
       Scanner input = new Scanner(System.in);
       
       int n = input.nextInt();
       
       if(n==1)
            System.out.println("-1"); 
       else{
           if(n%2 == 0 && n<5)
              System.out.println(n + " " + n);
           if(n%2 == 0 && n>5)
              System.out.println((n/2) + " " + (n/2)); 
           if(n%2 !=0)
              System.out.println(((n/2)+1) + " " + ((n/2)+1)); 
       }  
    }  
}