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 A {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        int x  = in.nextInt();
        int a=0, b=0;
        boolean w=false;
        for (int y=2; y<=x; y++){
            if(w!=true) {
                for (int i = 2; i <= x; i++) {
                    if (i % y == 0) {
                        if (i * y > x && i / y < x) {
                            a = i;
                            b = y;
                            w = true;
                            break;
                        }
                    }
                }
            }else{
                break;
            }
        }
        if(w){
            System.out.println(a + " " +b);
        }else{
            System.out.println("-1");
        }
    }
}