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:
n=int(input())
def find(n):
    x=1
    if n==1:
        print(-1)
        return()
    for a in range(1,n+1):
        for b in range(1,a+1):
            if a*b>n and (a/b)<n and a%b==0:
                print(a,b)
                return()
                
    
find(n)