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:
class ehabAndAnotherConstructionProblem:
    def __init__(self, x):
        self.x = x
        self.findTwoNumbers(self.x)

    def findTwoNumbers(self, x):
        c = 1
        l = 1
        for i in range(1, x+1):
            for j in range(1, x+1):
                m = i
                n = j
                q = m//n
                if((m % n == 0) and ((m*n) > x) and (q < x)):
                    if(l == 1):
                        print(m, n)
                        l = 2
                    c = 2

        if(c == 1):
            print("-1")


x = int(input())
if(1 <= x and x <= 100):
    pass
else:
    exit()
ehabAndAnotherConstructionProblemObj = ehabAndAnotherConstructionProblem(x)