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

        int x = scanner.nextInt();

        for (int b = 1; b <= x; ++ b){
            for (int a = b; a <=x; ++ a){
                if (a%b == 0 && a*b > x && ((a)  / b) < x){
                    System.out.println(a + " " + b);
                    return;
                }
            }
        }
        System.out.println("-1");

    }
}