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:
from sys import stdin, stdout

x = int(stdin.readline())
ok = False
for b in range(1, x + 1):
    for d in range(1, x + 1):
        if d * b <= x and d * b * b > x:
            ok = True
            break
    if ok:
        break
if ok:
    stdout.write("{} {}".format(b * d, b))
else:
    stdout.write("-1")