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:
x = int(input())
n = 0
k = 0
for i in range(x+1):
    if k == 0:
        for j in range(x+1):
            if (i and j > 1) and (i and j <= x) and (i % j == 0) and (i * j > x) and (i // j < x):
                print(i, j)
                n += 1
                k += 1
                break
    else:
        break
if n == 0:
    print('-1')