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.*;

public class cf525_1 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int a=0,b=0;
		boolean bo=false;
		for(int i=1;i<=n;i++) {
			for(int j=i;j<=n;j++) {
				if(j%i == 0) {
					if(j*i > n && (j/i) < n) {
						bo=true;
						a=j;
						b=i;
					}
				}
			}
		}
		if(bo == false) {
			System.out.println(-1);
		}
		else {
			System.out.println(a + " " + b);
		}
	}

}