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:
p=0
n=int(input())
if n==1:
    print('-1')
else:
    for i in range(2,n+1):
        for k in range(1,n+1):
            if i*k>n and i%k==0 and i*k>n and i/k<n:
                print(i,k)
                p=1
                break
        if p==1:
            break