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.BufferedReader;
import java.io.InputStreamReader;

public class CF1088A {

    public static void main(String[] args) throws Exception {
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        StringBuilder sb = new StringBuilder();
        int N = Integer.parseInt(in.readLine());
        int ansX = -1;
        int ansY = -1;
        for (int a = 1; a <= N && ansX == -1; ++a) {
            for (int b = 1; b <= N && ansX == -1; ++b) {
                if( a%b == 0 && a*b > N && (0.+a)/(0.+b) < (0.+N)){
                        ansX=a;
                        ansY=b;
                }
            }
        }
        if(ansX == -1)
            sb.append("-1\n");
        else
            sb.append(ansX+" "+ansY+"\n");
        System.out.print(new String(sb));
    }
}