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:
def solve(num):
    # if num == 1:
    #     return [-1]
    for i in range(1, num+1):
        for j in range(1, num+1):
            if i % j == 0 and i * j > num > i // j:
                return [i, j]

    return [-1]

print(*solve(int(input())))