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())
def gen_divider(chislo):
    for i in range(chislo, 0, -1):
        if chislo % i == 0:
            yield i


def res(x):
    for i in range(x+1):
        chislo = gen_divider(i)
        for j in chislo:
            if   1<=i<=x and 1<=j<=x and i*j > x and i/j < x:
                print(str(i)+" "+str(j))
                return
    print("-1")

res(x)