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:
import math as mt
import itertools as it
import functools as ft
import random as rnd

stdin = lambda type_ = "int", sep = " ": list(map(eval(type_), input().split(sep)))
joint = lambda sep = " ", *args: sep.join(str(i) if type(i) != list else sep.join(map(str, i)) for i in args)

x = int(input())

for a in range(1, x + 1):
    for b in range(1, x + 1):
        if a % b == 0 and a * b > x and a / b < x:
            print(joint(" ", [a,b]))
            exit(0)
print(-1)