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:
#coding: UTF-8

x = int(input())

ret = '-1'

if x < 1 or x > 100:
    x = 1

for a in range(1, x+1):
	for b in range(1, x+1):
		if (1 <= a and a <= x) and (1 <= b and b <= x) and (a % b == 0) and ((a*b) > x) and ((a/b) < x):
			ret = str(a) + " " + str(b) 
			break
						
print (ret)