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:
inV = int(input())
a = -1
b = -1
def calculate(x):
    if x > 100 or x < 1:
        print(-1)
        return
    satisfied = False
    for i in range(1,x+1):
        for j in range(1,x+1):
            if ((i % j) == 0) and ((i*j) > x) and ((i/j) < x):
                a = i
                b = j
                print(a, b)
                satisfied = True
                return
    if not satisfied:
        print(-1)
        return
calculate(inV)