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:
x = int(input())
resposta = list()
for a in reversed(range(1, (x) + 1)):
  for b in range (1, x + 1):
    if (a%b == 0) and (a*b > x) and (a/b < x):
      resposta.append(a)
      resposta.append(b)
      break
    else:
      pass
if len(resposta) > 1:
  print(resposta[0], resposta[1])
else:
  print(-1)