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:
t = int(input())
lst = list()
for i in range(1, t+1):
    for j in range(1, t+1):
        if (j%i==0) and (i*j > t) and (j//i< t):
            lst.extend([j, i])
            break
    if lst != []:
        break     
if lst == []:
    print('-1')
else:
    print(str(lst[0])+ ' ' + str(lst[1]))