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 PYTHON):

Solution:
def bettersearch(x):
  if (x == 1):
   return -1
  elif (x == 2 or x == 3):
    o  = str(x) +" " + str(x)
    return o
  else:
   for n in range(x+1):
     for m in range(x+1):
       y = int(x/3) + m
       z = int(x/2) + n
       if z%y == 0 and z!=y:
        if z*y > x:
          if y/z < x:
            o = str(z) +" " + str(y)
            return o
            break

   return -1     
x = int(input())
print(bettersearch(x))