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:
value = int(input())

def function(x):
	a = x
	b = 1
	while True:
		if a == 1:
			return -1

		if a*b > x:
			if a%b == 0:
				return a,b
			else:
				a-=1
		else:
			b+=1
		

result = function(value)
if type(result) is int:
	print(result)
else:
	print(*result)