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.*;

import javax.swing.plaf.synth.SynthSpinnerUI;
public class A {

	public static void main(String[] args) throws Exception{
		Scanner sc=new Scanner(System.in);
		int n=sc.nextInt();
		for(int i=1;i<=n;i++) {
			for(int j=1;j<=n;j++) {
				if(i%j==0 && i*j>n && i*0.1/j<n) {
					System.out.println(i+" "+j);return;
				}
			}
			
		}
		System.out.println(-1);
		
		
	}
	
}
class Scanner{
	StringTokenizer st;
	BufferedReader br;
	public Scanner(InputStream system) { br = new BufferedReader(new InputStreamReader(system));}
	public Scanner(String file) throws Exception{br = new BufferedReader(new FileReader (file));}
	public String next() throws IOException{
		while (st==null|| !st.hasMoreTokens()) st = new StringTokenizer(br.readLine());
		return st.nextToken();
	}
	public int nextInt() throws IOException{
		return Integer.parseInt(next());
	}
	public long nextLong() throws IOException{
		return Long.parseLong(next());
	}
	public String nextLine() throws IOException{
		return br.readLine();
	}
	public Double nextDouble() throws IOException{
		return Double.parseDouble(next());
	}

}