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.*;
 
public class Main
{
	public static void main(String[] args) {
		//System.out.println("Hello World");
        Scanner scan=new Scanner(System.in);
        int x=scan.nextInt();
        int a,b;
        if(x%2==0){
            a=x;
            b=x;
        } else {
            a=x-1;
            b=a;
        }
        if(a*b>x && a/b<x)
            System.out.println(a+" "+b);
        else 
            System.out.println("-1");
	}
}