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:
#!/usr/bin/python3

from sys import exit

def rint():
    return int(input())

def rints():
    return [int(s) for s in input().split(' ')]

x = rint()

for a in range(1, x+1):
    for b in range(1, x+1):
        if a % b != 0:
            continue
        if a * b <= x:
            continue
        if a / b >= x:
            continue
        print(f'{a} {b}')
        exit(0)

print(-1)