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:
line = int(input())

for i in range(1, line + 1):
    for g in range(1, line + 1):
        if i * g > line:
            if i / g < line:
                if i % g == 0:
                    if g % i == 0:
                        print(str(g) + ' ' + str(i))
                        exit()
print("-1")