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