# List of bounties with no deadline

This is a list of unofficial, deadline-less (hence not searchable) bounties offered by users on various challenges on the main site.

Disclaimer: There is no guarantee that the user will award the bounty for you in case you fulfill its requirement. Especially if the user isn't an active member anymore. The only guarantee is his/her written word.

# Guidelines for updating

• Answers can be commented on, allowing someone to notify the bounty's creator that the bounty may have been earned.
• If a bounty is awarded, delete the answer.

• How do you have a bounty without a deadline? – Beta Decay Jul 5 '15 at 18:11
• @BetaDecay They're unofficial bounties - if and when the feat is accomplished, a bounty will be created and the rep will be awarded. – isaacg Jul 5 '15 at 19:16
• This would be much more useful if people posted answers as answers rather than editing them into the question. That way when I see that it's changed I could just look at the answers sorted by activity (which is my default sort order on PPCG) rather than having to view the edit history of the question. – Peter Taylor Jun 30 '16 at 7:34
• There's a TNB feed for these bounties now. In order to pick your bounty up, you have to add an answer to this question. Question edits and answer edits won't be picked up by the feed. – Dennis Oct 22 '16 at 17:36
• Would it help to have a stack snippet in the question that just lists the first line of each answer as a link, rather than keep editing? – trichoplax Oct 23 '16 at 22:23
• Bounties that are only present in the meta question, and not posted as separate meta answers, leave no way to contact the bounty poster when time comes to claim the bounty. Please consider posting an answer if you have a bounty offered that doesn't yet have a meta answer. – trichoplax Oct 24 '16 at 0:49
• 100 Rep for a <100 byte answer to this question – Gryphon Jun 14 '17 at 14:17
• @JonathanFrech Fixed. – ASCII-only Jan 3 '18 at 8:50
• @Gryphon Post the bounty in an answer, not a comment. – mbomb007 Apr 30 '18 at 21:56
• Since the problem of stuff being posted in the question wasn't fixing itself, I've taken extreme action. If people want to sort bounties by amount offered, there are plenty of stack snippets which produce a table based on the answers: one of those can be adapted. Similarly, checking whether users are "active" or "passive" can be done with the SE API. – Peter Taylor May 7 '18 at 10:34
• @PeterTaylor It should be noted that not all the bounties in the question had corresponding answers, so you may have removed some completely. – mbomb007 May 10 '18 at 20:34
• @mbomb007, I checked the first dozen manually and then I counted and reasoned that since there were considerably more answers than lines in the question I was wasting my time. – Peter Taylor May 10 '18 at 22:40
• @PeterTaylor As an example, randomra had some bounties, but this search shows he has no current answers. Maybe you could write a script? Or ping everyone who had a bounty in the question, and they can deal with their own bounties. – mbomb007 May 11 '18 at 3:25
• I wish a bounty on Windows Batch/VBScript answers – Wasif Mar 24 at 15:50

# 50+ rep whenever you outgolf xnor

I've reached 100K and it's time to gift it back! I offer +50 rep to any new answer that outgolfs one of mine.

Rules

• Submit an answer that's shorter than mine and in the same language to a code golf challenge.
• It's fair game to shave bytes off my code after you look at it. Post an answer with your improvement.
• Any code golf answer of mine is eligible if it's at least one hour old and from 2016 or later.
• Only your new answers count, that is, those posted after this bounty.

I'm trying convey my intent with these rules, but it's up to my judgment what qualifies or not. Feel free to ask if unsure. Some further details:

• Even saving 1 byte counts. I may award a larger bounty for bigger golfs, or those that are particularly interesting or well-explained.
• "Cheap" golfs don't count. This means those mainly due to a different language version, looser I/O, or a changed or clarified spec. Remember that liberal I/O defaults weren't always a thing. Where I say I'm purposely avoiding some method or library, your answer needs to do so too.
• Non-code-golf challenges don't qualify.
• If you further golf someone else's answer that already outgolfed me, I'll decide case-by-case whether to award another bounty.
• Where I have answers in different languages to a question, these count separately.

Please edit in bounty claims here.

Bounty claims

• Idea: give rep in proportion to how much was golfed off. Scale so 1 byte off is 50 rep and all-but-one byte is 500 rep. – Adám Dec 5 '19 at 8:59
• @Adám I had considered doing some sort of minimum byte save or scaling, but decided to just offer 50 rep for any golf and make it a judgment call what to give more for. – xnor Dec 6 '19 at 5:29
• Does this count? It's shorter than many of your solutions (just not the shortest), and I think it's an interesting golfing trick – pxeger May 14 at 19:57
• @pxeger Gonna say no for that one, since my shortest solution was 42 bytes. Nice trick though! – xnor May 15 at 4:13

# Fitting but Unsuitable Languages: 1 x 500 points

There are some challenges for which we all want to see answers in a certain language, even if the solution is very difficult. I'll award 500 points for an answer in such a language to any.

### Gravity Simulator in Marbelous

Current shortest solution: 157 bytes in JavaScript ES6 using regex.

I don't know if this is even possible in Marbelous, a Turing-incomplete language, so I'd be very happy to see a solution.

### Minify Brainfuck in Brainfuck (Claimed by Mitch Schwartz)

I'm willing to give thousands more rep away in bounties of this type, so comment below to suggest challenges!

• Afaik, Sparr has some plans to make Marbelous TC. Is the third bounty still up if he does? – Martin Ender Jan 28 '16 at 16:16
• I'll need to know the details of the new features first, but probably. – lirtosiast Jan 28 '16 at 16:45
• I’m guessing the TI-BASIC program can’t just print out the answer? :P Also, is OS version 5.2 (84+CE only) allowed? There are some new string commands that would be helpful. – Hactar Oct 4 '16 at 12:34
• I noticed also that you were offering a bounty here. I'm not sure if you are still offering it as a bounty, but if so, adding it here might help it get noticed. – miles Oct 14 '16 at 8:46
• someone did the brainfuck one – Destructible Lemon Oct 28 '16 at 9:47
• What about trying this challenge in Cubix? Probably impossible – FlipTack Dec 25 '16 at 11:03
• Oh, never knew there was a Help! My calculator broke! challenge. At first I thought this was my Help! My calculator malfunctions! challenge that was linked.. – Kevin Cruijssen Sep 6 '18 at 13:27
• Maybe [this] answer is interesting. Brainfck to Unary-digits answered in Brainfck and Unary-digits. [this]: codegolf.stackexchange.com/questions/52712/… – Dorian Jun 4 '19 at 7:55
• I suggest Mowing the grass in Grass – wastl May 9 '20 at 14:15
• I suggest Error 404: Character Not Found in Intel 4004 machine code. – user96495 Aug 13 '20 at 5:13
• I have an answer to Output Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo in Buffalo. (Not sure this fits what you're looking for - it was pretty easy.) – Dingus Jan 31 at 22:44
• Hi I would like to claim the final bounty: codegolf.stackexchange.com/a/223001/96393 – user197974 Apr 7 at 4:47

# 1000 – 2000 rep for figuring out how to program with both halves of a Stack Cats program

This bounty needs a bit of background, so bear with me.

Stack Cats is an esolang with fairly strong constraints on its program structure. Specifically, each valid program has to have mirror symmetry, and the commands are designed such that mirroring a character results in the inverse operation. That means that the second half of the program (disregarding the character in the centre) exactly undoes what the first half did. So in a way it's on that central character to change the program state in a meaningful way, such that the undoing part actually results in the program behaviour you want.

Of course, there's only a handful of possible commands that can even be used for that single central character. For the mathematically inclined, this means that programming in Stack Cats is all about finding a conjugate relation that transforms one of 12 built-ins into the program you want to write. Nevertheless, I believe that Stack Cats is in fact Turing-complete.

While I've written non-trivial programs in Stack Cats (for example this primality test), they all rely on a certain construction that essentially works around these limitations, by skipping the entire first half of the program. This lets us put arbitrary "unbalanced" code in the second half, so we don't really have to worry about the conjugation. The basic construction looks like this:

<(...)*(...)>


The () are conditionals, which are always false in the first half and always true in the second half, so the first ... is skipped and the second ... is executed. The problem is that this is clearly inefficient for golfing: we could be doing useful stuff with both halves of the program, but we're just throwing one half away to be able to make sense of the program in the first place.

For very trivial problems, Sp3000 and I have found some programs that don't use this construction, but even those were usually found by an automated search. Here is an example of that for adding two numbers. In particular, our brute force approaches are usually nowhere near fast enough to find solutions that actually require control flow/loops. As far as I know, the only program that was ever written which uses both halves and contains a loop is this program by feersum (and given that the task was to implement an arbitrary OEIS sequence, it's likely that they just tried some programs with loops until one of them produced a reasonable OEIS sequence).

So, Sp3000 and I will together award 1000 rep to a Stack Cats answer, which:

• Contains non-trivial control flow, i.e. (...) and/or {...} which don't always do the same regardless of program input (in particular, if there's a (...) it should be executed for some inputs and skipped for others, to make sure that it isn't used to skip unused parts of the code unconditionally).
• Contains an explanation for how one can find such an answer without resorting to automated search (of course, you're perfectly welcome to make use of automated searches to get a better understanding of the structure of Stack Cats programs).
• Can't be easily outgolfed by an answer which uses the <(...)*(...)> template or which uses no control flow operations at all (to ensure that the program isn't just a linear solution like the addition program, padded with some loops which don't end up doing anything; and also to ensure that this technique actually makes use of both halves in an efficient way).

To be clear, the explanation is the most important part: this bounty isn't for finding such a solution by serendipity but for understanding how to construct such a solution.

Don't try to find loopholes in these rules — we're in no obligation to actually hand out the bounty, so if we feel like your answer is clearly not in the spirit of this bounty, we won't award it. I'm pretty sure that any answer which actually deserves the bounty, will do so quite obviously. Also, if you can solve several challenges (which are sufficiently different) with your technique — which would be a great proof that it's actually a general technique and not just a way to solve one particular task — we will award another 1000 rep to a second answer.

# 1000 + 500 Rep for a meta answer that solves the popularity problem

Popularity contests have been discussed many times, always with much conflict over what counts as a pop con, whether they should be on topic, whether the rules need to be consistent between different pop cons, and with a frustrating lack of consensus.

Justin is offering 1000 rep in bounties, and trichoplax is offering a 500* rep bounty for a solution to this.

The bounties will be posted on a challenge of the answer author's choice if a meta answer presents a solution to this and meets the following conditions:

• 3 popularity contests appear on main following the new meta answer, each of which after 30 days from posting has net 10 upvotes and is open.

The meta answer can be attached to a new meta question or an existing meta question.

The bounty target can be an existing challenge or a future one (the bounty can be deferred if the challenge is yet to be posted). It can be any challenge type.

The meta answer can make the rules on pop cons more restrictive, less restrictive, or any other combination of changes, provided it meets the voting criteria specified above.

There can be an arbitrary delay between posting the meta answer and the arrival of the 3 popularity contests on main.

*The 500 rep bounty was originally offered to any solution to the popularity problem, including a meta answer with the required support that bans popularity contests altogether. Such an answer will still earn a 500 rep bounty from trichoplax, but the main wording of this post has been edited to reflect what is required in order to win both bounties. Aside from an outright ban, any other solution will not be eligible for the 500 rep bounty until the required popularity contests have appeared on main.

• I'd add another 1000 rep on top of this. My terms might be slightly different in determining if someone solves the problem, but overall it would be basically the same – Justin Jul 2 '17 at 0:12
• @Justin I'd be interested to hear your terms. If they are similar enough, we can match our terms to each other and offer a combined bounty. If they are not, we can still offer two similarly themed bounties - either in separate answers here or in one answer with two descriptions. The advantage of a separate answer is that it makes it easy to ping the appropriate person to claim the bounty, but since you've commented here we should both be pingable on this answer now, so I don't mind either way. – trichoplax Jul 2 '17 at 7:52
• I guess I want to reserve the right to delay the bounty until we see a few fixed popularity contests get reasonable reception. I really don't want to give out the bounty unless people can make good challenges from the new scheme (because otherwise it didn't work IMO) – Justin Jul 2 '17 at 8:01
• That sounds like an excellent condition - it is indeed effectiveness rather than popularity that I wish to reward. I'd be happy to adjust my wording to include that. To make it precise I guess we could specify something like "N popularity contests posted after the date of the answer, each open with M net votes a month after posting each question". – trichoplax Jul 2 '17 at 8:10
• So if someone suggests banning pop-cons with community support that is now ineligible? – Wheat Wizard Jul 2 '17 at 13:51
• @EinkornEnchanter Dang I didn't think about that. While that's not the solution I want, it could be a solution. It's possible that we should special case that. OTOH, there have been a lot of popcons, which shows that people like them. It might be reasonable to not allow banning them as a solution unless the person also comes up with a similar challenge style which captures the "general feeling" of popcons (by community consensus ofc) – Justin Jul 2 '17 at 15:05
• @EinkornEnchanter I edited out the mention of banning popcons because it isn't compatible with the requirement for 3 new popcons, which I agree is a better way of measuring it. I could add back in that meta consensus banning popcons will still earn my original 500 rep bounty, but I didn't give it much thought because I thought it very unlikely that such an answer would be able to gain the 90% support specified. – trichoplax Jul 2 '17 at 17:06
• @Justin just to let you know I've edited to reflect this, but I'm fairly sure this has no effect on your bounty. Feel free to edit if it does. – trichoplax Jul 2 '17 at 17:15
• Posting this to make a record of my decision. While I'd prefer a solution that didn't ban popcons, I do have to accept that banning them is a possible solution. I don't want to promise that I'd award the bounty if banning is the solution, but it's very likely that I will – Justin Jul 2 '17 at 23:54
• I believe this is impossible. :P – Christopher Jul 26 '17 at 20:25
• @Christopher I'm inclined to agree, but I'd love to see someone prove me wrong, and happy to give up the rep if they do – trichoplax Jul 26 '17 at 20:52
• I don't think this is possible - not because the problem is unsolvable, but because I don't think it's reasonable to expect the voting restrictions. Why does it matter what the votes are on any popcons that follow our proposal? – Esolanging Fruit Oct 4 '17 at 5:28
• @Challenger5 The voting requirements on main were added to ensure that the proposal is effective, rather than simply popular on meta. – trichoplax Oct 8 '17 at 1:55
• @Challenger5 The meta answer can be posted on any meta question, possibly a new question. Obviously posting it on a relevant meta question will make it more likely to gather the required votes. From the answer: "The meta answer can be attached to a new meta question or an existing meta question." – trichoplax Oct 8 '17 at 1:56
• Hoping to try this again – Christopher Jan 22 '18 at 18:29

# 50 – 500 rep for an APL answer

I will reward 50 rep if all of the following conditions are met:

1. The answer is in Dyalog APL Classic/Unicode/Extended/Prime, APL2, APL+, APLSE, GNU/APL, Sharp APL, sAPL, SAX, NARS, APLX, A+, dzaima/APL, ngn/APL, APL\iv, Watcom APL, or APL\360. Feel free to suggest additional languages along this theme.

2. The challenge had no previous answer in any of the above languages.

3. The challenge was posted no later than on 31 Dec 2020.

4. The answer was posted after this bounty was set.

5. Awarding the bounty will not cause my rep to be under 10000.

Hint: Bubbler's SEDE query for eligible questions (has arbitrary filters and ordering — fork and edit if you want!)

The amount will be doubled once for each of the following conditions that are met (or 500 whichever is less):

1. The answer is well explained (as judged by me)

2. It is the poster's first APL answer, but the poster is not a "👋︎ New contributor".

3. The answer wins the challenge when posted.

## Bounty list

Awarded bounties are struck-through.

Bounties in progress are bold.

Bounties on hold are italic.

If you have previously requested a bounty, add can add more requests after the struck-through ones, otherwise add add yourself to the below list to request a bounty.

The format is:

- [username](url-to-profile): [rep](url-to-answer-post), [rep](url-to-answer-post)

## APL resources

### Other

• APLcart — collection of APL phrases

• APL Wiki — lots of info, including learning resources

• Do not leave a comment to request a bounty! Rather, edit the Bounty requests list in the post itself. – Adám Apr 10 '19 at 15:28
• SEDE query for searching questions eligible for this bounty. I did impose several arbitrary filters and ordering, so feel free to fork and edit for your tastes. – Bubbler Nov 20 '19 at 8:56
• I just checked and now you have more than 30 chat lessons, right? Might be worth editing that? – RGS Feb 12 '20 at 17:14
• @RGS Updated and added a couple of new links. Thanks. Also, congrats on winning the first 400 bounty! – Adám Feb 12 '20 at 22:53
• What's the reason for the "👋︎ New contributor" restriction? – S.S. Anne Mar 26 '20 at 22:10
• @S.S.Anne Preventing people from creating new accounts to get the multiplier. – Adám Mar 26 '20 at 22:41
• All of your challenges deserve an APL answer... – user92069 Apr 29 '20 at 1:41
• I believe Sherlock9's answer that you say is on hold due to invalidity has actually been fixed in revision 7 if you look at the history. – pppery Jun 30 '20 at 2:54
• @pppery Well spotted. – Adám Jun 30 '20 at 3:47
• WOW there is so much arrangement to make users learn APL, kudos to you @Adám, I am also interested in learning it now (was not interested before), where I can find starting tutorials for APL? – Wasif Mar 23 at 9:35
• @Wasif I suggest you come hang out in the APL Orchard, but learning resources are available at apl.wiki/Learning_resources. – Adám Mar 23 at 10:05

### 200 for beating the existing winner of Shortest universal maze exit string

The current winner has an exit string of length 79. A valid answer including code and a resulting exit string of length 78 or shorter will win the bounty.

The bounty will be awarded to the best answer when no better answer/edit has been posted for 7 days.

## 500 to 2000 rep for a quine in Hexagony

There are two ways to write a quine in Hexagony (which will probably result in very different solutions). The former is clearly the golfier version but the other one would be a lot neater. I'll give a 500 rep bounty to the first person who manages to write either of those:

• One program which is a quine when written most compactly, without whitespace and without unnecessary no-ops at the end (no-ops to pad the grid to the correct side-length are fine). (I have written one in the meantime but I'm happy to be beaten. You'll have to beat it at least by one side-length to qualify for the full bounty though.) This one has been awarded to Jo King's quine.
• I, (Jo King), will pass the 500, as well as 500 of my own rep to an even shorter quine. Again, you'll have to beat it by at least one side length to qualify (though a quine of the same side length that employs a sufficiently different algorithm may also qualify). The bounty has been claimed (in record time too!) by user202729's size 11 answer.
• Since the shortest Hexagony quine is now of side length 10, I (Jo King) will be awarding a bounty of 1000 for a shorter quine that beats it by at least 11 bytes (i.e. one row of the hexagon). If you can't quite get it that short, I will still award a 500 rep bounty for a side length 10 that uses a sufficiently novel algorithm. If you manage to golf another side length I will award 2000 rep (and my undying adoration)
• One program which is a quine when laid out nicely in a hexagon as usual, without a column of leading spaces and without any trailing spaces on the lines. There may be an optional trailing linefeed.

There should be some effort to golf the solution. And of course, the empty program is not a valid quine (I don't think there are any other possible cheats in Hexagony).

# 100-200 rep for good answers in interesting new languages

This is a bit subjective of course, but here are my criteria:

• The language is fairly new, and is interesting (in my opinion)
• The answer is clever, shows a lot of work put in, and shows off many features of the language (so no trivial posts in interesting languages)
• I have not awarded this bounty in a while (since I don't have much rep)

No requirements on what type of language (esoteric, golfing, practical, etc.). Doesn't have to be an answer by the language creator. I'm always interested in new languages, so if you think your post or someone else's deserves this bounty, leave a comment!

Awarded:

• would be a good idea to include some examples of any recent languages you find interesting. – Razetime Sep 25 '20 at 5:42
• also, it's hard to find out when a person gave away a bounty, so instead set a reputation limit, like if your reputation goes below 5500, then bounties are closed. – Razetime Sep 25 '20 at 6:42
• @Razetime I'm going to be adding a list of awarded bounties so people know when the last ones have been awarded. I won't set a hard limit for minimum rep I have, since that increases pretty quickly. As for recent languages I find interesting, I'll look into finding an example. – Redwolf Programs Sep 25 '20 at 12:30
• I think printLine("Hello, World!") is quite boring, so I'm assuming I don't qualify for this bounty... – Recursive Co. Apr 19 at 18:52

I don't like seeing good questions go unanswered, so I'm offering 200 rep each for valid answers to unanswered non- questions with a score of 20 15 or above. As of now (October 2020), there are 4 such questions:

You can check for yourself what questions are available via search, or vote for questions that are close to the vote count

### Previous winners:

• I offer 100 rep each for answering unanswered code-golf non-tips questions with any score, as long as there's a serious attempt at optimization. – lirtosiast Jul 1 '19 at 15:49
• Auto batch golfer now has an answer – EdgyNerd Aug 29 '19 at 7:00
• I didn't get bounty rep for my answer. The bounty ended with no winning answer. codegolf.stackexchange.com/posts/73230/revisions – Kamila Szewczyk Sep 6 '19 at 13:38
• Somebody answered the gerrymandering one! – PkmnQ Apr 9 '20 at 3:37
• For Complement POSIX ERE, you can check out the solutions for a simpler regex flavor. – Bubbler Aug 6 '20 at 9:07
• Successfully tiled my kitchen – Bubbler Oct 5 '20 at 4:19

# 200 rep for Vyxal answers

I'm basing this off the Japt bounty, so some of the wording is going to be the same

Vyxal has managed to get 25 stars on GitHub without much usage on the site. Let's change this by providing an incentive to answer! If any of y'all posts 5 Vyxal solutions in a 30 day period (starting from when this bounty was posted), Razetime and I will give you 200 reputation.

The 5 answers have to be posted after 20/04/2021 (UTC).

We'll be monitoring new solutions and keeping the list at the end of this answer updated but if we miss a solution of yours, please leave a comment with a link to it, or ping us in the Vyxal chatroom.

I (lyxal) will be doing my best to curtail my own Vyxal posts for at least the 30 days from 20/04/2021.

Bounties will be suspended if rewarding the bounty dips our reputation below 10k. If, on the off-chance, this bounty proves to be popular enough, we may adjust the rep we award to avoid completely tanking it.

Now go forth and dominate the competition and get this language onto the ELO list!

### Bounty Claims

Format:

- **[Username](code golf user profile)**: [1](link), [2](link), [3](link), [4](link), [5](link)


# Build a faster Quine, 1100* reputationClaimed by ais523

A bit to my surprise my recent bounty on Fastest Mini-Flak Quine expired without anyone other than myself completing the challenge. Since I think this is a legitimately fun and interesting challenge I would like to offer further incentive for participation. Thus 100 reputation will be awarded to anyone who can beat my Quine in runtime.

100 reputation will be awarded to the first person to create a faster Quine in Mini-flak than the current answer and post the answer on the appropriate question. An additional 1000 rep will be awarded to anyone that manages to beat the current answer using a novel method (not a variant or improvement on any existing Mini-flak Quine).

If the first prize is awarded but not the second the additional 1000 reputation will be left open to anyone who can beat the winner of the first 100 with a novel method.

I, WheatWizard, reserve the right to improve my own answer at any time, thus making this bounty more difficult to attain (It really isn't that difficult to attain in the first place).

The 100 reputation bounty will be awarded by 1000000000 and the 1000 reputation bounty will be awarded by WheatWizard.

* Up to 1100 but as little as 100

• You have to double the reputation amount (up to the limit of 500) every time you re-bounty a question, so the minimum for the next one would be 200. – Dennis Jan 27 '17 at 1:59
• Sure, that works. – Dennis Jan 27 '17 at 2:13
• OK, now that the reputation I got from the answer has given me sufficient rep to comment on Meta: I believe I qualify for the full 1100. You were right, it genuinely is a legitimately fun and interesting challenge. – ais523's temporary account Dec 3 '18 at 8:10

# 500-1000 rep for further work on (-a) × (-a) = a × a

This now classic question has 3 answers at score 18. Is 17 possible?

• 500 rep will be awarded for an answer with score 17 or lower.
• 500 rep will be awarded for strong evidence that a solution is optimal, with a possible additional bonus for a proof.

These bounties can be awarded either together or separately.

# 100-500 rep for APL answers to Bubbler's challenges

To celebrate me (Bubbler) reaching 25k rep (with over 100 answers in APL, 50 challenges written, and several thousands of rep gained from Adám's APL bounties), I will share some of my rep for even more APL answers!

Specifically, I offer 100 (or higher up to 500, depending on how impressive it is) rep for the following:

## A competitive APL answer to one of my code-golf challenges which doesn't yet have one

"Competitive" is a bit subjective, but it generally means the solution

• is at least shorter than comparable solutions in general-purpose languages (e.g. Python/JS; from my experience, APL usually gets 50~70% byte count of Python for moderately hard challenges, and much lower for easier ones),
• The code length is just a rule-of-thumb guide, and can be dismissed depending on the task (e.g. if the task makes it hard to use the SBCS).
• utilizes core APL features as appropriate, and
• does not look like a line-by-line translation from C or Python code.

If you think your answer is good but too long, you may ask for help at the APL Orchard for golfing. I will decide on the bounties based on the golfed answer.

In order to prevent rushing for the newest challenges, only challenges that are at least 2 months old are eligible for this bounty. This is also applied to the SEDE query below. Due to lack of interest, I decided to simply remove this condition.

### List of challenges to answer (SEDE query)

These challenges (despite having an APL answer already) are also available for the bounty:

• (none at the moment)

Note that some of the challenges are also eligible for Adám's bounties. Feel free to claim both.

## Bounty Requests

• Is this bounty still going? I'm thinking about answering the C variable declaration question, but it since it looks a bit hard, I'd like some fake internet points too :) – user Dec 2 '20 at 21:21
• @user Of course it is still going. (I just paused to give out LotM bounties, but forgot to resume this one after the LotM ended) It's great that you're tackling one of the harder problems, which is exactly what I was wishing for with this bounty. – Bubbler Dec 3 '20 at 2:22
• Oh, cool, thanks. It’s really great that you and Adam are giving out these bounties to encourage people to learn APL. – user Dec 3 '20 at 3:00

# 100 rep for Making a calculator in GNU sed

Considering it is hard to even make addition in GNU sed, It is definitely worth a bounty.

• I accept the challenge. What should be a minimum precision for division? This is not specified there. Also, do you have a time limit for a calculation? I ask because my submitted sed answer for the 1/x challenge takes an incredible amount of time to finish, but is theoretically correct. – seshoumara Apr 9 '17 at 19:12
• @seshoumara 4 under floating point/fractional output – Matthew Roh Apr 10 '17 at 7:28
• – mbomb007 Apr 30 '18 at 21:31
• @mbomb007 Re "If you didn't cheat, it would fulfill a bounty. This needs to be deleted unless you fix it.": OP are not forced to award the bounty if they think that it doesn't deserve it anyway. – user202729 May 15 '18 at 7:51
• Exactly. So if the person fixed their program, it would win the bounty. – mbomb007 May 15 '18 at 13:16
• I know I'm late, but there's a sed calculator here: sed.sourceforge.net/grabbag/scripts/dc.sed – ThePlasmaRailgun Jun 25 '19 at 22:02

# 150 rep for a shorter C quine

Currently, the shortest known C quine (written by me) is 64 60 bytes. I will give 150 rep to anyone who tops this.

Rules:

• Must be a full program (include the main function, or otherwise define main)
• Cannot use the filename to store data
• Cannot pull data from the internet
• Cannot read its source nor its executable (thanks, Dennis)
• Must be more than 1 byte (bytecount includes flags)
• Must be system-independent (you may assume POSIX and ASCII)
• ... strictly more? Or at least? (anyway it's easily verifiable whether there is a 1-byte quine) – user202729 Jan 21 '18 at 9:51
• @user202729 do you have a proper 1-byte quine? – MD XF Jan 21 '18 at 19:36
• Does X count (must be compiled with -DX=main()puts("X");)? – NieDzejkob Feb 18 '18 at 18:48
• @NieDzejkob No, that's a standard loophole. – MD XF Feb 18 '18 at 18:53
• @MDXF so if flags used, what to output? – l4m2 May 8 '18 at 1:21
• @l4m2 If flags are used it's not just "C language", it's "C language with flags". – user202729 May 15 '18 at 7:43
• @user202729 Must be more than 1 byte (bytecount includes flags) – l4m2 May 15 '18 at 9:31

# 500 rep for a shorter payload capable V quine

Currently in V, there are two important quines:

2i2i


is the shortest known quine, but not modifiable. And

ñéÑ~"qpÿ


is the shortest known trivially modifiable quine. This is because

ñéÑ~"qp<CODE>ÿ


pretty much anything you want can go in the place of CODE, and it will still be a valid quine. You can see this on these answers:

Although these used a former version of the extensible quine, namely:

ñi<C-v>241<esc>"qpÿ


Either one could be easily modified to use this newer quine. Another good example is filling CODE with 'l's should always work. I will award this bounty to the first user to find a shorter extensible quine. For the purpose of this bounty, extensible means that any code you want to add to it will be recorded into some register and then pasted later, which is how the current solutions work (into register 'q' FWIW).

For completeness sake, I have found several 8-byte solutions:

ñéÑ~"qpÿ
ñéÑ~"qpx
ñéÑ~"qðÿ
ñéÑ~"qðx
ñ"qpÁÑ~x
ñ"qpÁÑ~ÿ


And many more trivial modifications that aren't worth posting. If you'd like more explanation on any of these, or want more examples, feel free to ping me in TNB or Vim-Golf.

# 100-500 rep for answers to good, old questions with few answers

Disclaimer: I'm putting this bounty on hold until I reach 10k rep (or 4 months, whichever is less), mostly because I'm greedy

This bounty is for answers to questions that meet the following criteria:

• They have a score of 10 or more (and fewer than 4 downvotes)
• There are between 1 and 9 answers (inclusive)

I won't award this bounty if doing so makes me drop a privilege level.

For questions not tagged , here are the bounty amounts, depending on how many answers there are and whether or not there is a good explanation:

• 1 to 3 answers (inclusive): 400 rep (500 with a good explanation)
• 4 to 6 answers: 200 rep (300 with a good explanation)
• 7 to 9 answers: 100 rep (200 with a good explanation)

This search from caird coineringaahing/ChartZ Belatedly may help find eligible questions.

For questions tagged , if there are 5 or fewer answers already, new answers can get 50 rep.

Please edit in your requests in the form username: [amount](answer link), [amount](answer link). Bolded requests are in progress, and those that are struck through have finished.

rak1507: 250, 300

ChartZ Belatedly: 500, 200why not 300?, 400, 400

Wasif: 200, 300, 300, 200

Jonah: 200

pxeger: 300

Razetime: 200

Dion: 200

# 100 rep for a neural network (or other new thing) that writes Moby Dick

This will be awarded in Write Moby Dick, approximately when one of the following conditions is met:

• an answer is posted based on neural networks and gets a reasonable score. (It doesn't need to compete with the top answers, just do reasonably well.)

• an answer is posted that takes a different method from the existing answers, in my subjective opinion. All the current top answers use variations on a Markov model (i.e. store substrings of length n and guess the most common next letter); I'm looking for an answer that does something significantly different from this. As above, this should score reasonably well but need not compete with the top answers.

• an answer is posted that (a) uses a sophisticated method (in my subjective opinion), and (b) has a good explanation of that method, where "good explanation" means I could implement it myself without reading the code. This bounty could be awarded to an existing answer, if one is updated with a good explanation.

• Uh... -2. It seems that the community doesn't like it. – user202729 Jan 21 '18 at 9:48
• @user202729 that's... odd. But never mind, they don't need to - the bounty is between me and whoever would like to compete for it. – Nathaniel Jan 21 '18 at 10:33
• Unclear what you're asking. No objective winning criterion. – mbomb007 Apr 30 '18 at 21:34
• @mbomb007 don't need one. It's a bounty. My rep, my discretion. – Nathaniel Apr 30 '18 at 22:43
• I'm saying that's why it's downvoted. It's a really unclear bounty. Poorly worded. – mbomb007 Apr 30 '18 at 23:00
• @mbomb007 your opinion is noted, but I don't share it, and I don't care about the downvotes in the slightest. – Nathaniel May 1 '18 at 5:45
• This looks like a job for Andrej Karpathy's Magical LSTM. – Nissa Sep 10 '18 at 19:00

# 500 rep for outscoring in Multiply with restricted operations

The current best score is 22 operations.

itx = 1/(1+a+b)     #4
nx = -1/(itx+itx)   #4
c = -( 1/(itx + itx + 1/(1+nx)) + 1/(1/(a+nx) + 1/(b+nx)) ) #14


Try it online!

I'll give 500 rep to the first better score, that is 21 operations or fewer.

Alternatively, you can get the bounty by proving that 22 is in fact optimal, say with exhaustive search. A weaker proof or lower bound can get a partial bounty.

# 100 bounty: Minecraft redstone prime checker

What it says on the tin.

My version of a valid prime checker uses:

• levers as input (ON = 1, OFF = 0), representing a binary number
• redstone lamp as output (ON = prime, OFF = not prime)

I offer 100 reputation to make an expandable prime checker - that means that you can expand the prime checker in any direction infinitely, with minimal redstone wiring (connect the two "modules" together using redstone) and the prime checker still works.

You are allowed to use any block except for structure blocks and command blocks.

Do I need more clarification?

• It is trivial to make a non-expanable that only takes one or two bits. (or probably any non-expandable for that matter). I don't want to tell you what to do with your rep but something tells me you might want to add a lower bound or remove the non-expanable category. – Wheat Wizard Oct 30 '16 at 23:50
• @WheatWizard That's a good point... fixing right now. – clismique Oct 31 '16 at 7:01
• Can we use command blocks? structure blocks? If not could you include a specification for what blocks we can or cannot use. – Wheat Wizard Nov 3 '16 at 15:03
• where do I post? – tuskiomi Nov 17 '16 at 21:01
• @tuskiomi Post it on "Is this number a prime?" (link here). – clismique Nov 18 '16 at 0:20
• @tuskiomi Do you have a working prime checker? – clismique Nov 24 '16 at 7:27
• @WheatWizard Fixed that. – clismique Nov 24 '16 at 7:29
• Would a 32 bit prime checker be eligible for this bounty. Or is the expandable thing something you are set on. – Rohan Jhunjhunwala Dec 24 '16 at 1:50
• @RohanJhunjhunwala I would say you only get the rep if you make it "expandable". Making it non-expandable is much easier compared to the "expandable" thing. – clismique Dec 24 '16 at 3:07
• @Qwerp-Derp so would writing a prime checking program for the Universal turing machine be considered expandable if increased input could be realized with more blocks on the tape. – Rohan Jhunjhunwala Dec 24 '16 at 13:38
• @RohanJhunjhunwala No, because that's not really "expandable" - my definition of expandable is that two or more copies of the same prime checker, with minimal redstone wiring, should act as a bigger prime checker. I should probably clarify that. – clismique Dec 24 '16 at 13:41
• IS this possible? – Rohan Jhunjhunwala Dec 24 '16 at 13:51
• @RohanJhunjhunwala That's why I'm offering a bounty for it. Besides, nothing's impossible on PPCG. I mean, look at Dennis's answers in Jelly. – clismique Dec 24 '16 at 13:52
• I have partial progress. It's definitely possible, but the amount of time required is a barrier. I'm open to someone helping me. chat.stackexchange.com/transcript/message/34627269#34627269 – mbomb007 Jan 18 '17 at 16:40
• Maybe you should make your restriction "theoretically rebuildable in Survival", that would exclude functions, cmd block minecarts, falling_block storing a cmd block, stuff in stored hotbars, etc. – Fabian Röling Oct 18 '18 at 18:16

# 500-2000 reputation for a golfy language

This bounty will be awarded to a new golfing language (more precisely, to an answer in that language by its author to Showcase of Languages) that

• Bests all pre-2019 languages by 10% or 2 bytes (whichever is greater) in 10 pure challenges.
• The 10 challenges must be a subset of 100 consecutively posted challenges from before February 11, 2019.
• No challenge of the 10 is written by the the language's author.
• Is on TIO.run.
• Has available documentation.
• Is otherwise sufficiently non-cheaty (at my discretion). Huffman coding is okay; builtins that don't generalize are not.
• All of the above remain true for 1 week.

The bounty amount doubles for every additional 10% improvement up to a 2000 rep, so a language that improves on all pre-2019 languages by 30% in each of the 10 challenges will be awarded the maximum 2000 rep; a 15% improvement nets 700 rep, and so on.

• @A_ This is about language design, so to be eligible you must make significant contributions to the language. – lirtosiast Sep 29 '19 at 18:27
• @A_ Consecutively posted challenges are consecutive on codegolf.stackexchange.com/questions?tab=Newest. You must be the overall winner on each challenge by 10%, so if the shortest solution in a pre-2019 language is 22 bytes, your answer should be 19.8 bytes or shorter to count as one of the ten. Tying a pre-2019 language will mean that challenge doesn't count as one of the ten, but doesn't count against you. – lirtosiast Oct 1 '19 at 15:02

# 900 rep for a shorter Klein Topololyglot

What it says on the tin, beat the current best and I'll give you 400 rep. (and 500 from me, Jo King)

Previous winners:

• What if we prove yours is optimal? – lirtosiast Jul 13 '17 at 22:23
• @lirtosiast Personally I doubt it is, but a proof of optimality is also worthy of the bounty. – Wheat Wizard Jul 14 '17 at 1:39

Similar to this offering, I will offer varying amounts of reputation for answers to questions that meet the following criteria:

• The question is at least one month old
• The question has a net score $$\\ge3\$$ and $$\\lt 15\$$
• The question is not tagged
• The question is open

*: Unanswered means that no answers have been posted to the question which fully complete the task in the question

This list of questions, sorted by current score, can be found here.

The amount of reputation I will offer depends on the following criteria:

• Age of the question (older questions will merit more rep)
• How impressive I personally find the answer (based on language, score etc.)
• How difficult I perceive the challenge to be

Obviously, these are subjective, but I will try to be as fair as I can.

Furthermore, if awarding a bounty will drop me below a privilege level, causing me to lose it, I will postpone awarding the bounty until I have enough rep to avoid this. However, such bounties will only be postponed, so all valid answers will eventually receive their deserved bounties.

To claim a bounty, as normal, ping me in chat or leave a comment below. If unable to do so due to reputation requirements, ask another user to do so for you, so I don't miss any answers.

Once you claim one of these bounties, please edit it in below

## Claimed bounties

• @Wzl That's incorrect - there's nothing about views in the bounty, and you're missing created:...1m, which is in the query already in the answer. I did forget it should be -[tips] instead of -tips tho, thanks! – caird coinheringaahing Jun 9 at 1:31

# 500 rep - Bubblegum Factorial

Bubblegum is designed for constant output - unless the code has a specific SHA-hash, you won't be able to write a program which takes input.

So, I will award 500 rep for a factorial program in Bubblegum. I don't really expect this to be fulfilled, as it requires major advances in cryptography to be possible.

If anyone ever completes this, post it as a submission to the Factorial challenge, where I will award the bounty.

• So if someone solves decrypting SHA-256 this they could either decide to grab 25 bitcoins or get 500 reputation points on stackexchange. – dylnan May 1 '18 at 2:49
• @dylnan ... Why not both? ;) – DLosc May 15 '18 at 2:15

# 400 reputation for an answer to Paint Starry Night that takes top place without built-in compression

The bounty will be awarded to the first answer that takes first place (i.e. lowest score) without using an off-the-shelf compression routine. I'll award it even if it's immediately beaten by another answer. Currently the score to beat is 4159.06.

# 100 rep for a Haskell answer to "Make me some curry"

I'll offer a 100 rep bounty for a Haskell answer to the above mentioned challenge. I might offer more than 100 rep for an interesting answer (for example not just copying the Idris answer or a clever TH answer).

Given that tuples are tricky with Haskell and that you can't use lists (can only contain one type), feel free to define your own data-type or use an appropriate one from an existing library on hackage.

Note: This bounty is tied to the one below, if someone gets the second bounty I will delete this one!

# 200 rep for a low-level answer (machine language, C or similar)

I'd love to see an answer that's really low-level, that's the main reason I allowed taking the number of arguments as input because otherwise it seems impossible.

• For an answer in machine language, I need some way to know the type (or actually just the size) of the arguments. May I assume all arguments are of some constant size or may I get a list of argument sizes as extra argument? – wastl Sep 21 '19 at 1:03
• Hi, is this bounty still going? I've posted a Haskell answer to that question. – user Sep 13 '20 at 0:01

# 500 rep for a ridiculously huge number

There are currently no valid answers to Golf a number bigger than Loader's number. This bounty will be awarded to the valid first answer that either

• Is under 256 bytes, or
• Outputs a number significantly larger than Loader's number (i.e. larger than any simple modification to loader.c).
• 256 bytes? Wow, that thing would probably win Bignum Bakeoff when it was made earlier. – Naruyoko Apr 30 '19 at 0:15

# 250 rep for continuing One OEIS after another

The last answer to this challenge was posted on March 6, 2018, meaning that the contest has been long over. However, I'm offering 250 rep to the next answer, A, posted to this question that meets the following conditions:

• The answer is valid, according to the challenge rules
• There are at least 3 answers posted to the question after A before a month has passed (to ensure the chain is actually revivied, even for a little bit)
• Offering the bounty does not cause me to lose a site privilege
• In this case, I'll simply delay offering the bounty to a point where I won't lose a privilege, but the bounty will (eventually) be awarded

Beyond these three conditions, any answer is acceptable. Don't bother leaving a comment below, I'll be notified if/when an answer attempting to claim this bounty is posted

# 100-500 rep for solving challenges using an ACE exploit in an esoteric language

I've reached 2300 rep, so here's a bounty for you RE/CTF enthusiasts for an answer I really want to see.

CVE-2018-6849: Code execution results in code execution
TheZZAZZGlitch, "A friendly reminder: Lua scripts are arbitrary code", YouTube

Esoteric language interpreters and compilers are often pretty shoddily written. It is usually shrugged off because "nobody is going to use it for anything serious".

1. Find an existing interpreter, translator, or compiler for an esoteric language published before January 2021. Preferably, this should have an entry on esolangs.org or be under the "Recreational" category on TIO.
2. Find a bug in the interpreter, compiler, or generated code that allows you to escape the language and execute arbitrary code. This can be direct code execution, launching a shell, cross-site scripting, return oriented programming, making compilers emit arbitrary code, or something similar. If you can execute arbitrary code in the compiler itself, that counts as well.
3. Explain the bug (and, preferably, explain a way to fix it if it hasn't been patched)
4. Solve a code challenge posted before January 2021 using code executed from that exploit instead of the tools provided by the language.
5. Also be sure to explain the payload itself.

To be clear: You are only allowed to use features provided by the language to set up the payload and exploit. The logic to solve the puzzle must be entirely in the payload.

However, you are allowed to execute some code from the interpreter/compiler itself in the payload, e.g. for input and output or ROP chaining.

The following do not count:

• Exploits that just run the interpreter on arbitrary code in the same language. You must demonstrate full control over the interpreter.
• Exploits caused by the code you wrote. The code you wrote must only exploit the bug.
• Tools in the language intended to execute code (e.g. execve()/system() in C or things like eval()).
• Bugs in third party code or the programming language that the interpreter/compiler uses. (e.g. exploiting a Node.js bug in an interpreter written in JavaScript)
• Code challenges that are simply "crash the program" or the like: It should be something interesting.

Older releases of an interpreter/compiler are fine.

Since these are very system specific, please either provide an online demo or a Docker image. You are required to provide the exact build instructions in the latter case.

Custom compiler flags for building interpreters follow the same loophole rules.

See some of my answers for Shortest code that raises a SIGSEGV which highlight some interpreter bugs I found for a starting point.

While I may not be able to award immediately, I will try to award anywhere from 100-500 rep, depending on how much you impress me. Finding new exploits is strongly encouraged instead of using the same one over and over.

Take that Phooey freebie while you can!

Add a comment here or ping me in chat if I (likely) don't notice your post.

• Good point. I will allow compilers/transpilers. – EasyasPi Jan 24 at 22:52
• I have clarified that it should be an esoteric language, which wasn't obvious before. – EasyasPi Jan 25 at 0:20

# 50-500 rep for answers to Bubbler's challenges in any of previous LotM languages

LotM languages often go inactive again after the event ends, so here is an attempt to keep them alive (or revive?).

I (Bubbler) will award 50-500 rep for answering one of my , non- challenges in previous LotM languages.

An answer is eligible for this bounty if:

• the challenge is , non-, and at least a week old (search query),
• the language used was on LotM before,
• there isn't another endless bounty that awards answers in that language (so Whispers and Vyxal are out), and
• the challenge didn't have any other answer in the same language before it.

Also, if you have 5,000 rep or higher, I won't award the bounty for solving Easy or Medium challenges.

The bounty value will be decided as follows:

• Base value (depends on the language used)
• +50: Brachylog, MATL, Japt, R, Husk, Rust, Scala, Factor
• +100: QBasic, Forth, Vim
• +200: Brain-Flak, SMBF
• Multiplier (depends on the difficulty of the challenge)
• ×0.5: Easy
• ×1.0: Medium
• ×2.0: Hard
• ×4.0: Insane
• Extra bonus (additive) if the answer is exceptionally good or interesting to me

### Notes

• I won't award the bounty if the value goes below 50 (or the minimum value I can award on the challenge), and the bounty value is capped at 500.
• I don't have a fixed difficulty assigned to my challenges (yet). I'll try to be consistent though. You may generally assume a challenge is at least Hard if it has relatively high score and very few answers (and definitely Easy if it has very many short answers).

• (none yet)

## Bounty Requests

• Please edit in bounty requests here below the template, with relevant links.
• (none yet)
• Template: [Username](link): [Answer](link) to [Challenge title](link)