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
nmbr=lambda:int(stdin.readline())
lst=lambda:list(map(int, stdin.readline().split()))
for _ in range(1):#nmbr()):
    n=nmbr()
    if n==1:print(-1)
    else:print(n,n)