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
from math import sin, tan, cos, pi, atan2, sqrt, acos, atan, factorial


n = int(stdin.readline())
label = 0

for a in range(1, n + 1):
    if label:
        break
    
    for b in range(1, a + 1):
        if a % b == 0 and a * b > n and a // b < n:
            stdout.write(str(a) + ' ' + str(b))
            label = 1
            break

if not label:
    stdout.write('-1\n')