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 ans(x):
    for a in range(x, 1, -1):
        for b in range(a, 1, -1):
            if a % b == 0 and a * b > x:
                return [a,b]
    return [-1]
x = int(input())
numbers = ans(x)
if len(numbers) == 1:
    print(-1)
else:
    an = str(numbers[0])+" "+str(numbers[1])
    print(an)