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 newSc = new Scanner(System.in);
        int n = newSc.nextInt();
        if(n > 1){
            if(n % 2 == 0)
                System.out.printf("%d %d\n", n, 2);
            else
                System.out.printf("%d %d\n", n - 1, 2);
        }
        else
            System.out.println(-1);

    }
    }