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Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

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Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#101
post #62

Earlier quoted context omitted.

Not necessarily. If they insist on there being only 12 puzzles, all they need to Save Christmas is to start the event on Christmas day, and rename it to "12 Puzzles of Christmas" or "Advent of Three Kings of Code", or such -- see: https://news.ycombinator.com/item?id=45710963 .

They could also publish the puzzles only every second day, I guess.

That was my first thought too, and I'd prefer it, cause sometimes I'll get stuck on a problem, or I'm busy, or I forget, and I'd rather have one more day. Bur it's Eric's call in the end.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#102

Whenever there's a change like this, my gut reaction is to grieve and try to imagine ways that things could be kept the same. After thinking, "maybe puzzles could be designed by a group instead of an individual and they could share the work," I then thought, "and couldn't an LLM help?" And with that, I had to remind myself: Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has…

> And with that, I had to remind myself: Advent of Code isn't about there being 25 puzzles Really? The name of the event is "Advent of Code". Having 25 puzzles is easily its most strongly-determined aspect. You could argue for 23-29 puzzles, or perhaps for 5, but at 12 what's the name supposed to refer to?

I assumed it was "twelve days of Christmas"- related

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#103

Earlier quoted context omitted.

If I were Christmas of code, it would start mid-June and end on Christmas Eve!

You're forgetting about Halloween, Black Friday/Cyber Monday, and the most recent Singles Day (11.11); the Commercial Calendar is steadily squeezing the Christmas Season into December and out of the rest of the year!

Commercial Halloween starts during October just after or parallel with October-fest. It ends before end of October because people buy things for an event before it starts. End of Halloween is when Commercial Christmas starts.

There is no time for actual advent or winter calmness in general.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#104

Whenever there's a change like this, my gut reaction is to grieve and try to imagine ways that things could be kept the same. After thinking, "maybe puzzles could be designed by a group instead of an individual and they could share the work," I then thought, "and couldn't an LLM help?" And with that, I had to remind myself: Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has…

Hate to be the... whoever I'm being right now, but names have meaning. It's the reason to have them in the first place. > Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has nothing to do with it. It's the Advent of Code. Not "Random late year event with no religious / commercial tradition connotations whatsoever" of Code. The 25 is there in the name. It's the whole point :).

If, as you claim, the association of 25 to "advent" is primarily commercial, that's much more of a reason to avoid that association. In any case it's very culture-specific. In many countries, including mine, Christmas Eve is the "main" event that people look forward to, and the number of "advent days" in calendars and such is 24. On the other hand, ecclesiastically there are four Advent Sundays, and the number of days is thus variable and also not really pertinent.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#105

A little sad for me because I've enjoyed the global leaderboard aspect for years but of course my second reaction has to be to take a step back and appreciate all the joy that this one man has given us for all these years. And he's made it clear from that start that he never intended the global leaderboard to be the point, plus AI the last few years messes it all up. All good things come to an end, and I gotta apprec…

Based on time-zone, it wasn't really global.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#106
post #58

I see the leaderboard is gone too. Unfortunate but entirely predictable given how the last 2 years went. That being said, I was worried he'd cancel the entire thing, so this is still good news!

>predictable given how the last 2 years went QRD? Was it AI?

Yeah, a bunch of people started going on witch hunts against the people where were obviously using AI (eg ~30 second solve times) and also anyone who had "AI" anywhere in their bio.

IMO the levels it got to was wildly out of proportion, even if these people were cheating (say what you will about AI, but if the rules say not to use it and you do: you're a cheater) but maybe I would have felt differently if the timezones meant I could take part, rather than waking up to drama.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#107

Whenever there's a change like this, my gut reaction is to grieve and try to imagine ways that things could be kept the same. After thinking, "maybe puzzles could be designed by a group instead of an individual and they could share the work," I then thought, "and couldn't an LLM help?" And with that, I had to remind myself: Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has…

Hate to be the... whoever I'm being right now, but names have meaning. It's the reason to have them in the first place. > Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has nothing to do with it. It's the Advent of Code. Not "Random late year event with no religious / commercial tradition connotations whatsoever" of Code. The 25 is there in the name. It's the whole point :).

There are tons of advent calendars commercially sold that have fewer than 25 slots.

It’s safe to say this ship has sailed.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#108

Whenever there's a change like this, my gut reaction is to grieve and try to imagine ways that things could be kept the same. After thinking, "maybe puzzles could be designed by a group instead of an individual and they could share the work," I then thought, "and couldn't an LLM help?" And with that, I had to remind myself: Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has…

Hate to be the... whoever I'm being right now, but names have meaning. It's the reason to have them in the first place. > Advent of Code isn't about there being 25 puzzles, and so maintaining volume at all costs has nothing to do with it. It's the Advent of Code. Not "Random late year event with no religious / commercial tradition connotations whatsoever" of Code. The 25 is there in the name. It's the whole point :).

> The 25 is there in the name.

This largely depends on who you're asking? I don't know anyone who wouldn't consider 24 the course correct number of Advent, simply because that's the common number here (we celebrate Christmas on the 24th). So 12 makes perfectly sense, just do every second day.

There are also many groups who don't start on the 1st of December, but on the first Sunday of Advent. And probably many others.

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#109
post #9

Earlier quoted context omitted.

I’ve been trying to design a puzzle for a game this year that humans can solve but LLMs can’t. I’ve come up with one, but it was hard work! It’s based around message cracking.

There was one in a previous AoC that I think stumped a lot of AI at the time because it involved something that was similar to poker with the same terminology but different rules. The AI couldn't help but fall into a "this is poker" trap and make a solution that follows the standard rules.

Isn't that easily solved by changing the terminology before giving it to the LLM?

Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time

#110
post #29

Earlier quoted context omitted.

Twelve nights of Christmas. Would also work better for me, calendar-wise :)

This referes to the feast of the Epiphany, though, which is 12 nights after Christmas...

That's why I say it would've worked better for me, yes.
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