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:
from math import ceil, sqrt
x = int(input())
b = 1
for n in range(1,x+1):
	b = ceil(sqrt(x//n))
	a = n*b
	if a*b > x:
		break

if b != 1:
	print(a,b)
else:
	print('-1')