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 otra(x):
    if ((math.floor(x/2)+1)%2 == 0):
        print(str(math.floor(x/2)+1) +' 2')
    else:
        print(str(math.floor(x/2)+2) +' 2')
    return

if __name__ == '__main__':
    x = int(input())
    if x == 1:
        print('-1')
    elif 1 < x and x <= 100:
        otra(x)