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 Solution {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		int x = sc.nextInt();
		Boolean bool = true;
		outer: for (int a = 1; a <= x; a++) {
			for (int b = 1; b <= x; b++) {
				if (((a % b) == 0) && ((a * b) > x) && (a / b) < x) {
					System.out.println(a + " " + b);
					bool = false;
					break outer;
				}
			}
		}
		if (bool) {
			System.out.println(-1);
		}

		sc.close();

	}

}