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:
#one step form using ceil 
import math
x = int(input())
if(x == 1 ):
    print('-1')
    #sys.exit()

elif(x !=3):
 
    if(math.ceil(x/2)%2 == 0):
       #print('k')
       print(math.ceil(x/2)+2,2)
        
    else:
       print(math.ceil(x/2)+1,2)
else:
    print(3,3)