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:
# You'll never get ahead of anyone as long as you try to get even with him. Lou Holtz
# by : Blue Edge - Create some chaos

x=int(input())
i=1
while i<=x:
    if i*i>x:
        print(i,i)
        break
    i+=1

if i==x+1:
    print(-1)