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 search(x):
  if(x == 1):
    print(-1)
  else:
    a = 1
    while a <= 100:

      a += 1
      b = a
      while b <= 100:
        
        if (a > 1) and (b > 1) and (a <= x) and (b <= x) and (a % b == 0) and (a * b > x) and (math.floor(a / b) < x):
          
          print(a, b)
          a = 100
          b = 100

        b += b

search(int(input()))