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
from collections import defaultdict, Counter, deque

INF = float('inf')

def gcd(a, b):
	while b:
		a, b = b, a%b
	return a


def primeFactor(n):
	if n % 2 == 0:
		return 2
	i = 3
	while (i ** 2) <= n:
		if n % i == 0:
			return i 
		i += 1
	return n

def main():
	x = int(input())

	if x <= 1:
		print(-1)
		return
	print(x, x)
	return

if __name__ == "__main__":
	# t = int(input())
	t = 1
	for _ in range(t):
		main()