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:
n = int(input())
a1 = 0
b1 = 0
for a in range(1, n+1):
	for b in range(1, n+1):
		if a>=1 and b>=1:
			if a % b ==0:
				if a*b > n:
					if a / b < n:
						a1 = a
						b1 = b
if a1 ==0 and b1 == 0:
	print(-1)
else:
	print(a1, b1)