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:
import sys
import math
import bisect

def main():
    n = int(input())
    ans = None
    for a in range(1, n + 1):
        for b in range(1, n + 1):
            if a % b == 0 and a * b > n and a / b < n:
                ans = [a, b]
    if ans == None:
        print(-1)
    else:
        print('%d %d' % (a, b))

if __name__ == "__main__":
    main()