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:
def bruteForce(x):
  a = list()
  for i  in range(x,0,-1):
    a.append(i) 
  for i in range(x):
    for j in range(x):      
      if a[i]*a[j]> x and (a[i] % a[j]==0) and (a[i] / a[j] < x):
        return (str(a[i])+" " + str(a[j]))
  return -1       
a = int(input())
print( bruteForce(a))