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:
cin = lambda:map(int, input().split())
n, m = int(input()), 0
for a in range(1, n + 1):
	for b in range(1, n + 1):
		if a % b == 0 and a * b > n and a / b < n:
			print(a, b)
			m = 1
			break
	if m == 1:
		break
else:
	print(-1)