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 funcao(x):
    for a in range(1, x + 1):
        for b in range(1, x + 1):
            if (a % b == 0) and (a * b > x) and (a / b < x):
                return (a, b)
    return (-1, -1)

res = funcao(int(input()))

if res[0] != -1:
    print(str(res[0]) + " " + str(res[1]))
else:
    print("-1")