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:
import math

def solve(x):
	if x == 1:
		return -1, 
	else:
		return x - x % 2, 2

"""
def verify(x):
	a, b = solve(x)
	assert a <= x
	assert b <= x
	assert a * b > x
	assert a % b == 0
	assert a // b < x

assert solve(1) == (-1,)
for i in range(2, 101):
	verify(i)

"""
x = int(input())
print(*solve(x))