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 PYTHON3):

Solution:
#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Sun Mar 17 22:08:22 2019

@author: killmonger
"""

import os
import sys
import math
import collections
import cmath
def mp():
    return map(int,input().split())
def inp():
    return input()
n=int(inp())
if n==1:
    print(-1)
else:
    print(str(n)+" "+ str(n))