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:
strInp = lambda : input().strip().split()
intInp = lambda : list(map(int,strInp()))

x = int(input())
condition = False;
for i in range(x):
    for j in range(x):
        if (i+1) % (j+1) == 0 and (i+1) * (j+1) > x and (i+1)/(j+1) < x:
            condition = True
            break
    if condition:
        break
if condition:
    print(i+1,j+1)
else:
    print(-1)