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 operator import itemgetter
#int(input())
#map(int,input().split())
#[list(map(int,input().split())) for i in range(q)]
#print("YES" * ans + "NO" * (1-ans))
x = int(input())
if x == 1:
    print(-1)
else:
    print(x,x)