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_Ehab_and_construction {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
		int flag = 0;
		for(int i = 2 ; i <= x ; i++) {
			for(int j = 2 ; j <= x ; j++) {
				 if((i%j == 0) && (i*j > x) && (i/j < x)) {
					System.out.print(i + " "+ j);
					flag = 1;
					break;
				}
			}
			if(flag == 1) {
				break;
			}
		}
		if(flag == 0) {
			System.out.print(-1);
		}
	}

}