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:
num = int(input())

tof = True
for i in range(2, num + 1):
        j = i
        while (j<=num):
                if ((j%i==0) and (j*i>num) and (j/i<num)):
                        print(j, i, " ")
                        tof = False
                        break
                j+=i
        if (tof==False):
                break
if (tof):
        print(-1)