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:
num = int(input())
max_num = 0
min_num = 0

if(num == 1):
  print(-1)
elif(num <= 3):
  print(num, num)
else:
  for i in range(num, 0, -1):
    max_num = i
    for j in range(i-1, 0, -1):
      min_num = j
      if(max_num % min_num == 0):
        if(max_num / min_num < num):
          if(max_num * min_num > num):
            break
    if(max_num % min_num == 0):
        if(max_num / min_num < num):
          if(max_num * min_num > num):
            break
  print(max_num, min_num)