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