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.BufferedReader; 
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.util.Scanner; 
import java.util.StringTokenizer; 
  
public class Javademo
{ 
    static class FastReader 
    { 
        BufferedReader br; 
        StringTokenizer st; 
  
        public FastReader() 
        { 
            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 nextInt() 
        { 
            return Integer.parseInt(next()); 
        } 
  
        long nextLong() 
        { 
            return Long.parseLong(next()); 
        } 
  
        double nextDouble() 
        { 
            return Double.parseDouble(next()); 
        } 
  
        String nextLine() 
        { 
            String str = ""; 
            try
            { 
                str = br.readLine(); 
            } 
            catch (IOException e) 
            { 
                e.printStackTrace(); 
            } 
            return str; 
        } 
    } 
  
    public static void main(String[] args) 
    { 
        FastReader in=new FastReader();               
        int a,b,cnt=0,max=0,f=0;
        int x=in.nextInt();
        for(a=1;a<=x;++a)
        {
            for(b=1;b<=x;++b)
            {
                if(a%b==0)
                {
                    if(a*b>x)
                    {
                        if((a/b)<x)
                        {
                             System.out.print(a+" "+b);                        
                             f=1;
                             break;
                        }
                        if(f==1)
                            break;
                    }
                    
                        if(f==1)
                            break;
                }
                
                        if(f==1)
                            break;
            }
            
                        if(f==1)
                            break;
        }
        if(f==0)
             System.out.print(-1);                        
              

            
      
    }
}