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 geek {


    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        boolean flag=true;
     int x=s.nextInt();
     for(int i=1;i<=x;i++){
         for(int j=1;j<=x;j++){
             if(i%j==0){
                 if(i*j>x&&(i/j)<x){
                     System.out.println(i+" "+j);
                     flag=false;
                     break;
                 }
             }
         }if(!flag){
             break;
         }
     }if(flag){
            System.out.println("-1");
        }
            }

            }