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())

number_list = list(range(1, (x+1)))



ordered_pairs = []

for j in range(x):
    a = number_list[-j - 1]
    for i in range(x):
        b = number_list[i]
        if a % b == 0:
            if a*b > x:
                if a/b < x:
                    ordered_pairs.append([a,b])

#print(ordered_pairs)
if len(ordered_pairs) == 0:
    print(-1)
else:
    print(ordered_pairs[-1][0], end=' ')
    print(ordered_pairs[-1][1])