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 scan = new Scanner(System.in);
		
		boolean v = false;
		
		int x = scan.nextInt();
		
		scan.close();
		
		int i=0,j=0;
		
		
		for(i=2;i<=x;i++){
			
			for(j=2;j<=x;j++){
				
				if(i*j>x && i%j==0 && i/j<x){
					
					v=true;
					break;
					
				}
			
								
			}
			if(v) break;
			
		}
		
		if(v){System.out.println(i+" "+j);}
		else{System.out.println(-1);}
	}

}