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 s():
    x = int(input().rstrip())

    if x in (2, 3):
        print(2, 2)
        exit()

    adiv = lambda a: [x for x in range(1, a) if a % x == 0][::-1]

    for a in range(0, x+1):
        for b in adiv(a):
            if a*b > x and a//b < x:
                print(a, b)
                exit()

    print(-1)

s()