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
sys.setrecursionlimit(2000)
from collections import Counter

if __name__ == "__main__":

    # single variables
    n = [int(val) for val in input().split()][0]

    pair = None
    good = False
    for a in range(1, 200):
        for b in range(1, 200):

            if(a%b == 0 and a*b > n and a//b < n):
                good = True
                pair = [a, b]
                break
   
        if(good):
            break
 
    if(good):
        print("%d %d" % (pair[0], pair[1]))

    else:
        print("-1")