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:

# Main
def run():
    n = int(input())

    if n == 1:
        print(-1)
    else:
        found = False
        for i in range(1, n+1):
            for j in range(i, n+1):
                if j % i == 0 and j * i > n and j // i < n:
                    print(j, i)
                    found = True
                    break
            if found:
                break
        if not found:
            print(-1)

# end main


# Program Start
if __name__ == "__main__":
    run()