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(a):
    p = 0
    q = 0
    sign = 0
    for i in range(1, a + 1):
        for k in range(1, a):
            if i ** 2 * k > x:
                p = i * k
                q = i
                sign = 1
                return (p, q)

    if sign == 0:
        return (p, q)
           
x = int(input())
a = 0
b = 0
(a, b) = solve(x)
if a == 0:
    print(-1)
else:
    print(a, b)