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.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Main 
{

	public static void main(String[] args) throws NumberFormatException, IOException 
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int x = Integer.parseInt(br.readLine());
		
		for(int a = 1; a <= 100; a++) 
		{
			for(int b = 1; b <= 100; b++) 
			{
				if(a*b > x && a % b == 0 && a / b < x) 
				{
					System.out.println(b + " " + a);
					return;
				}
			}
		}
		System.out.println(-1);
	}
}