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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

#41

Post by rootlocus »

akerl_ wrote: post #34
HiPhish wrote: post #32

If he has cut the number of puzzles in half, why not then release a new puzzle every other day? That would make more sense because AoC would still run until Christmas, and it would give people more time per puzzle. Maybe unlock part 2 of each puzzle the day after the puzzle has been posted, so there still something new every day. I once tried participating, but gave up halfway through because one puzzle per day was j…

If they’re released every day for 12 days, you can do a puzzle every other day. If the were released every other day, people who wanted to do them for 12 straight days could not.

> If the were released every other day, people who wanted to do them for 12 straight days could not.

If they instead waited 12 days, they could start with the 6 puzzles already released, and then have enough puzzles to solve once a day for the next 12 days.

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

#42

Post by fud101 »

gf000 wrote: post #31
ekimekim wrote: post #9

Earlier quoted context omitted.

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.

I mean, wasn't pretty much the second half of all AoC exercises beyond LLM capabilities? I remember there being multiple accounts trying to one-shot AoC and all ended on day 10 or so.

[flagged]

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

#43

Post by Gigachad »

petesergeant wrote: post #8
thomascountz wrote: post #4

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…

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.

Have a look at https://arcprize.org/

They have hundreds of challenges that humans can solve in under a minute which LLMs can not. Seems the general trend is figuring out the rules or patterns of the challenge when there are few examples and no instructions.

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

#45

Post by 0x264 »

fjfaase wrote: post #17
nikanj wrote: post #5

Tryhards ruin everything, part n Make a fun little christmas calendar to bring joy to the people, get turned into a gamified warzone where people use AI and bots to try to get onto the global leaderboards - possibly because getting on them might net you a job at FAANG

The temptation to start a competative private leader board will be great, just for the mentioned reason. I have a reference my scores in my CV. The competative part of AoC is one of the things that I find attractive and also has taught me some valuable lessons about coding, like taking some time to review the code the first time before submitting. I experienced several times that I spend of time to debug a small bug…

On your CV ? Has any recruiter or hiring manager ever commented on it, or said the mention gave you an advantage ?

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

#46

Post by TeMPOraL »

thomascountz wrote: post #4

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 :).

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

#47

Post by petesergeant »

Gigachad wrote: post #43
petesergeant wrote: post #8

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.

Have a look at https://arcprize.org/ They have hundreds of challenges that humans can solve in under a minute which LLMs can not. Seems the general trend is figuring out the rules or patterns of the challenge when there are few examples and no instructions.

Ah, it also needs to be challenging for humans. It's a prize to win something. I just didn't want people to throw the question into Claude Code.

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

#48

Post by Udo »

nikanj wrote: post #5

Tryhards ruin everything, part n Make a fun little christmas calendar to bring joy to the people, get turned into a gamified warzone where people use AI and bots to try to get onto the global leaderboards - possibly because getting on them might net you a job at FAANG

I know this is an outsider position, but I always felt that the AoC leaderboard was a mistake. Very few people had the time, the commitment, and the capability of making it on there in a meaningful fashion, and it put an emphasis on something that didn't match the vibe of the event at all. If speedrunning the problem solving was the point, then why package every episode into an enjoyable little story?

This also ties into the comments that AoC has become moot or was "ruined by LLMs". If you enjoy solving the problems, nothing should have changed for you. What's the difference if a given problem was already solved by an LLM, or a group of IQ 200 superhumans from MIT for that matter?

As time marches on, there will eventually be absolutely nothing left where an unaugmented human outperforms a machine. That doesn't mean you have to stop enjoying things. In a few years at most, all programming will be purely recreational.

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

#49

Post by [deleted] »

TeMPOraL wrote: post #46
thomascountz wrote: post #4

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 :).

[deleted]

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

#50

Post by Scarblac »

rich_sasha wrote: post #24
shrx wrote: post #3

One of the reasons I stopped participating was that as the second half of december was approaching I had less and less free time for solving the puzzles. So to me it is also a welcome change, I will try to finish it again this year.

I once has this half serious idea to do "Advent of Parenting", with one problem per month, and you start after Christmas. As in, youre so delayed you start in the New Year, and have time for one problem per month. But hey I didn't have the time to do it. Kids...

When my kids move out, one of my plans is to finally start the first Advent of Code.
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