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