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())

found = False

for i in range (2, x):
  for j in range (i,x):
    if (j % i == 0  and j*i > x):
      found = True
      print(j , " " , i)
      break
  else:
    continue
  break

if(x == 2):
  print("2 2")
elif (not found):
  print(-1)