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:
x = int(input())

a, b = None, None
for i in range(1, x + 1):
	for j in range(1, x + 1):
		if(i % j == 0 and i*j > x and i//j < x):
			a = i
			b = j
			break
	if(a != None or b != None):
		break


if(a == None or b == None):
	print(-1)
else:
	print(a, b)