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 sys
input = sys.stdin.readline
from operator import mul
from functools import reduce
from sys import stdout

############ ---- Input Functions ---- ############
def inp():
	return(int(input()))
def inlt():
	return(list(map(int,input().split())))
def insr():
	s = input()
	return(list(s[:len(s) - 1]))
def invr():
	return(map(int,input().split()))

##############################################



###########  ----- MAIN FUNCTION ------  ##########
def main():
	n=inp()
	if n==1:
		print(-1)
	else:
		print(n,n)
 
if __name__ == "__main__":
	main()