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())
if(x == 1):
    print(-1)
else:
    a = x
    b = 2
    while(a >= b):
        if((a * b > x) and (a//b < x) and (a % b == 0)):
            print(a, b)
            break
        else:
            if(b + 1 <= a):
                b += 1
            else:
                a -= 1