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:
# ANSHUL GAUTAM
# IIIT-D

from math import *
from copy import *
from string import *
from sys import stdin
from itertools import *

x = int(stdin.readline())
ans = [-1]
for a in range(1,x+1):
	for b in range(1,x+1):
		if(a*b > x and a//b < x and a%b == 0):
			ans = [a,b]
			break
print(*ans)