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