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 JAVA):

Solution:
//var input = readline()
var num = readline()
var n = parseInt(num)

if(n==2 || n==3) print(2 +' '+ 2)
else if(n==4 || n==5) print(4 +' '+ 4)
else if(5<n) print(parseInt(n/2) +' '+ parseInt(n/2))
else print(-1)