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:
n = int(input())
a=0
b=0
v=0
if(n!=1):
    for y in range(1, n+1):
        for z in range(1,n+1):
            if(z%y==0)and(z*y>n)and(z/y<n):
                a=z
                b=y
                v=1
                break
        if(v==1):
            print(a,b)
            break
else:
    print(-1)