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.IOException;
import java.util.Scanner;

public class ProblemB {
	public static void main(String[] args) throws IOException {
		Scanner scan = new Scanner(System.in);
		int x = scan.nextInt();
		boolean sol = false;
		for(int a=1;a<=x;a++){
			for(int b=1;b<=a;b++){
				if(a%b==0 && a*b>x && a/b<x){
					System.out.println(a+" "+b);
					sol=true;
					break;
				}
			}
			if(sol) break;
		}
		if(!sol) System.out.println("-1");
		scan.close();
	}
}