Jimmy puts Ann's birthday present in a cuboid box. The dimensions of its edges are positive integers and the sum of its , , and is .
What is the maximum volume Ann's present box can have?
Input Format
A single integer, (the sum of the box's , , and ).
Constraint
Output Format
Print the maximum possible volume of the box.
Sample Input 0
4
Sample Output 0
2
Sample Input 1
8
Sample Output 1
18
Explanation
Sample 0
Here, our only possible dimensions are some combination of , , and . , so we print .
Sample 1
Here are all possible edge dimensions:
, .
, .
, .
, .
, .
We print the maximum volume, which is .