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 EhabAnotherConstruction {

	public static void main(String[] args) throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int num = Integer.parseInt(br.readLine());
		for(int i = 1; i <= num; i++) {
			for(int j = 1; j <= num; j++) {
				if(i%j==0) {
					if(i*j>num) {
						if(i/j<num) {
							System.out.println(i+" "+j);
							return;
						}
					}
				}
			}
		}
		System.out.println(-1);
	}

}