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:
def program(n):
    for i in range(n,0,-1):
        for j in range(2,n+1):
            if(i%j==0 and (i*j)>n and (i/j)<n):
                return (i,j)
n=int(input())
r=program(n)
if(r==None):
    print("-1")
else:
    print(r[0],r[1])