Resolvsed with actual random location tests.

Please could you run again to confirm that the issue has been dealt with?

I have removed the original test that used a bad randomising method. I have also implemented a new shape which is very large (111 a bit big I know but I will change kata description to match). This one makes use of completely random coordinates to test again as I cannot think of how to nicely and efficiently generate random shapes which do not overlap at this moment in time. I am sure if needed I can implement it, but for now it should be fine.

I will ensure that the tests are random. Thank you for making me aware.

The random tests are not actually random: see this

Resolved

function name should be snake_case

Resolved.

Alright my thought process was incorrect. Thanks for the fast response you are 100 % correct. I did not realise i and j can be the same to solve this. That was my problem. Resolved.

I just solved the kata in JS with my solution from other languages and I have no good idea what this issue is about. Everything seems to work as expected? Broken formatting in the original post is not helpful either.

I'm not really sure I understand your issue, but it seems like a code issue to me. You can represent 4 as 2 + 1 + 1, just like you can represent 16 as 8 + 4 + 4, and 256 as 128 + 64 + 64. I guess your assumption is wrong..?

According to instructions tests are invalid for 2 to the power of any number in JavaScript:

Write a function that accepts a number, and checks it can be represented as a sum of exactly 3 powers of 2. (n == 2i + 2j + 2**k, i, j, k >= 0)

--> Since 2 ** 0 = 1, then as far as I can tell you cannot have a value as true which is 2 ** i where i is the value that obtains the number in the test since then you still have + 1 and + 1 for + 2 extra. This needs to be dealt with since: "n = 4: expected false to equal true " is not correct nor 256 or 1024, etc <--

For example:

three_powers(2) # False
three_powers(3) # True, 3 = 20 + 20 + 20
three_powers(5) # True, 5 = 20 + 21 + 21
three_powers(15) # False
Input
1 <= n <= 2 ** 512 - 1
There are 100 performance tests in languages with arbitrary precision integers, and a huge amount in C/Lua.

Note to translators: this kata should NOT be translated into any languages without arbitrary precision integers, as the performance requirements are not guaranteed to be properly enforceable.

If you need I can provide my code for testing purposes since the only ones it fails are the ones which are incorrectly labeled as true for 2 to the power of a single value. Just tell me how.

Yes this helps, thank you

For 42 pieces you have 3 options since we are not including side length 1:
2 * 21
this option gives 0 inner pieces since every piece has a flat side. Therefore inner - outer = -42 . . .
3 * 14
This time the inner pieces are 1 * 12 which is 12. Total outer pieces are 30. so inner - outer = -18
6 * 7 . . .
there are 4 * 5 inner pieces for 20 inner and thus 22 outer pieces. 20 - 22 = -2
Most negative difference is -42 and most positive difference is -2 as it is the most positive of all of the options. Hope that helps.

So how do you explain this? Where does -42 and -2 come from?

n = 42 ==> [-42,-2]

This issue should now be fixed with the tests, but if I still have it incorrect and your solution is giving you difficulty just reply and I will get on it ASAP.