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

}
}