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;

/**
 * Created by Shahbaz on 04-Dec-18.
 */
public class Solution {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int x = sc.nextInt();
        int p=0,q=0;
        boolean found=false;
        for(int b=1;b<=x;b++){
            for(int a=1;a<=b;a++){
                if(b%a==0){
                    if((a*b)>x){
                        if(a/b<x){
                            found=true;
                            p=b;q=a;
                            break;
                        }
                    }
                }
            }
            if(found)
                break;
        }
        if(found)
            System.out.println(p+" "+q);
        else
            System.out.println("-1");
    }
}