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:
#constructionproblem

x = int(input())

b = 1

a = 1

vega = 0

vegb = 0

while(a <= x):
    while(b <= a):
        if(a % b == 0):
            if(a * b > x and a // b < x):
                vega = a
                vegb = b
        b = b + 1
    b = 1
    a = a + 1

if(vega == 0 or vegb == 0):
    print("-1")
else:
    print(vega, vegb)