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 cv=new Scanner(System.in);
        int n=cv.nextInt();
        boolean a=true;
        int k=n;
        for (int i = 0; i < n && a ; i++) {
            for (int j = 1; j <= n; j++) {
                if(k%j==0 && k*j>n){
                    System.out.println(k+" "+j);
                    a=false;
                    break;
                }
            }
            k--;
        }
        if (a){
            System.out.println(-1);
        }
    }
}