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 ehab_construction {
	public static void main(String[] args) {
	       Scanner sc = new Scanner(System.in);
	       int x=sc.nextInt();
	       int a=1,b=1;
	       
	       if(x==1)
	    	   System.out.println("-1");
	       else
	    	   System.out.println(x+" "+x); 
	       //for(a=1;a<=x;a++)
	       {
	    	   //for(b=1;b<=x;b++)
	    	   {
	    		   //if(a%b==0 && a*b>x && a/b<x)
		    	   {
	    			   
	    			  // System.out.println(a+" "+b); 
		    		   //break;
		    	   } 
	    	   }
	    	   
	       }
	      
	       
	}       
}