Feedback on the Second Coding Challenge

First off, I'd like to say that I find this challenge much more entertaining than the previous one, and that I'm super glad you decided to give us two weeks instead of one for it.

I know feedback is often negative, but efforts need to be pointed out, too! Kudos to y'all for listening to the community!

Some more feedback, though.

Interpretation problems

If you have chosen a board with very limited possible states (like tic-tac-toe) you can use sequential board states.

Should I understand that if the board I've chosen doesn't have very limited possible states, I can't use sequential board states? Is this a hard requirement?

How many possible board states would you consider "very limited"?

Your entry is not permitted to be written, in full or in part, by AI. AI assistance with coding or debugging is permitted if it is disclosed in your entry and the initial code is wholly your own.

I'm not sure I understand: "Your entry is not permitted to be written, in full or in part, by AI." (emphasises mine), meaning essentially that no code in my entry can come from an AI, even if it's just a small part of my codebase.

But, "AI assistance with coding or debugging is permitted" (emphasises mine), so I am allowed to have some of my code written by AI.

Wait, so am I allowed to use AI-written code or not? Don't get me wrong, I'm NEVER gonna use AI to code, but I wouldn't be surprised if I wasn't the only one to be confused by these two sentences that contradict each other.

What I would have done differently

The board state does not need to be a board state that is legal in the game you have chosen.

This is the only part of the challenge that I find a disappointing. Having to make the board state legal would have played a huge part into making this challenge interesting in my opinion, especially with the extended deadline.

There's 10 entries already as of writing, though, so it's too late to change that, but for future reference: this kind of criteria can be interesting.

General feedback

General feedback about Coding Challenges, and how it could be improved, is also welcome.

I'm confused by the "awards" given when challenges end. Challenge #1 claims awards have been given to the winners.

When I hear "award" on SO, I'm thinking about a badge, or rep, or anything really that you can find on someone's profile that show they legitimately won something.

In reality though, the "award" here is getting a nice title in the challenge's updated description. While it was agreed that no reputation would be given during this beta, badges were still mentionned. I'd suggest to either give (maybe temporary) badges, or some kind of icon (similarly to the trophy icon for big contributors to collectives), or to reformulate this from "awards" to some word that doesn't usually imply that something was given.

I submitted an answer using Conway's Game of Life. I could not submit what I wanted to originally as when I hit "Add", it responded with either the "Post must be less than 30000" message or then when I shortened it to the bare bones, "This looks like spam." As a result, I had to split the submission into a main post and then 2 replies (because the whole writeup without code apparently also looks like spam). I understand why you wouldn't want me to know what exactly triggers an anti-spam guard. However, maybe here are a few potential heuristics for you to fine tune:

• The text representation of the program (RLE file) and alternatives look like a wall of unreadable text with few unique characters.
• The write-up was long and required a lot of explanation and reference links.

Both of these naturally follow from programming with things that aren't text-based programming languages. I really don't feel good about just linking to a gist or repo for the same reason I have a problem with link-only-answers on the main site.

It's not exactly a conventional program, so I get it if this it's considered too small an edge case to fix. It was annoying to have this blocked, though, so I thought I'd mention it.

I also do have to wonder about whether the chances of getting spam are nearly as high on these as opposed to Discussions. Maybe it's worth relaxing some of these restrictions. E.g. the ability to add images, or at least upload from the editor and link to save vertical space, would also be nice on a challenge like this one where a game board is more readily understood visually.

Also, this challenge was way more interesting than the last one. Thanks.

I enjoyed the challenge, but I want to mention two things:

• I noticed that when you write a solution post, you don't see any preview.
• Also, there seems to be no syntax highlighting even when code blocks start with a language hint.

I dislike the general concept of hosting code challenges on SO, so my main feedback would be to get rid of that experiment. With that out of the way, here's some specific criticism of the current challenge:

• I would expect a "code challenge" to focus on, well, writing code. The challenge here is about steganography, hiding a message in a board game. At first glance, the primary goal of this challenge is to invent a clever way to map the state of a board game to a character set, so basically creating a mapping or algorithm for building a state from a message and reading a message from a state. All of that could be done in plain english and it's unclear why any code would be required at all, or what role the code should fulfill specifically.
• As people can choose any board game and any encoding, the solution space seems pretty big, which means comparing submissions to others is close to impossible. You acknowledge that your current way of simply counting upvotes to determine the best solutions is not good, but for a challenge this broad, you will never be able to find an objective way of judging.
• As you don't exclude scrabble, I forsee 275897823 entries with some variety of "simply write the message on a scrabble board", maybe in rot13 if someone is clever. There are also various other games which allow for trivial solutions (e.g. a 6 bit encoding in connect four). I don't see anything for weeding out trivial or troll submissions, which means you might get flooded in them and interesting submissions might get lost in the noise.

What character set is the domain for challenge 2? The larger the character set, the more states a solution needs to be able to support.

It will be nice for this challenge to enable us to include photos in the post. My solution encrypts using a Rubik's cube and it is hard to visualize without the colors.

Please state up-front in the challenge body next time if images aren't allowed. I chose an extremely creative interpretation of the challenge that depends on minute details in the image. No, it's impossible to visualize without images because it's designed to be completely independent of the textual board state. Now there is only irrelevant information shown:

It only uses relative distortions and positions, so it works equally well with any other board state and can't be visualized with text.

The introduction was originally going to catch peoples' attention by being unique, and now it just looks like a wall of text.

First of all I have to say that I really like the idea of the code challenges and this time it's really more interesting and entertaining than the first one.

My main point of criticism is the voting system. It's so hard and time consuming to look through all of the submissions choosing one to vote on.

It might be better that the SO staff is doing a preselection first after the deadline ends. Maybe the ten best submissions in staffs opinion but without revealing the staffs no. one choice.

The voting itself should only be possible after the staffs preselection is published.

I ran into another issue that my code was too long to post it in one go. Fortunately I could simply cut off my comments part at the beginning of the code and post it separately without breaking the code itself. Maybe it should be a general challenge rule that the code length must be 30k chars maximum.

"Cipher" and "encode" are not generic terms without specific meaning.

This challenge sometimes uses "cipher" and sometimes uses "encode" to describe the task. Encoding is a one-to-one mapping using a codebook, so the confidentiality of the message depends on keeping the codebook (i.e., the algorithm for computer encoding) secret. Encipherment scrambles the message using a key, which is usually shared out-of-band (i.e., not as part of the message), so the algorithm is public and the key is secret.

The challenge says nothing about a key. Is the challenge intended to include or exclude the use of pre-shared keys?

If there is no pre-shared key, then "inviting other users to crack" the so-called "cipher" amounts to reverse engineering the algorithm (because it's just a codebook). Is that the intent?

For example, DES and AES are ciphers. ASCII and Base64 are codes.

In composing this challenge, it would probably have been worthwhile to ask crypto.SE for suggestions to update/clarify the language. Meanwhile, what is the intent?

Can we use multiple board-state snapshots of the same type of game (for example: chess) to encode the message? Or, do we have to use a single-snapshot of the board-state alone?

The rules stipulated that the board-state does not have to be a legal state as per the rules of the game. If I were to use chess, does that mean I can use 64 pieces at max of any of the two colors, instead of just 16 + 16 = 32?