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 EhabConstruction{
	public static void main(String[] args){
		Scanner scan = new Scanner(System.in);
		int x = scan.nextInt();
		if(x<2){
			System.out.println(-1);
			return;
		}
		int a = (x/2)+1;
		if(a>=1){
			System.out.println(a+" "+a);
		}else{
			System.out.println(-1);
		}
		scan.close();
	}
}