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:
n = int(input())
enc = False
for a in range(1,n+1):  
  for b in range(a,n+1):
    if((a*b)>n and (b%a)==0 and int(b/a)<n):
      print(b,a)
      enc = True
      break
  if(enc):
    break
if(not enc):
  print(-1)