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 bruteforce(x):
  if (x == 1):
   return -1
  elif (x == 2 or x == 3):
    o  = str(x) +" " + str(x)
    return o
  else:
    x_list = []
    for n in range(x):
       x_list.append(n+1)
    for n in range(len(x_list)):
      for m in range(len(x_list)):
        y = x_list[n]
        z = x_list[m]
        if z%y == 0 and z!=y:
           if z*y > x:
              if y/z < x:
                 o = str(z) +" " + str(y)
                 return o

    return -1          

x = int(input())
print(bruteforce(x))