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())
a = 1
b = 1
while b <= x:
    if(a % b == 0 and a*b > x and a/b < x):
        print(str(a) + " " + str(b))
        exit()
    
    if(a == x):
        b += 1
        a = 1
        continue
    a += 1

print(-1)