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.*;
import java.io.*;
import java.math.*;
import java.awt.geom.*;

public class Test {
    public static void main(String[] args) {
        MyScanner sc = new MyScanner();
        int x = sc.ni();
        for (int i = 1; i <= x; i++) {
            for (int j = i; j <= x; j++) {
                if (j % i == 0 && i * j > x && j / i < x) {
                    System.out.println(j + " " + i);
                    System.exit(0);
                }
            }
        }
        System.out.println(-1);
    }

    /////////// TEMPLATE FROM HERE /////////////////
    private static class MyScanner {
        BufferedReader br;
        StringTokenizer st;

        public MyScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int ni() {
            return Integer.parseInt(next());
        }

        float nf() {
            return Float.parseFloat(next());
        }

        long nl() {
            return Long.parseLong(next());
        }

        double nd() {
            return Double.parseDouble(next());
        }

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }
}