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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

#131

Post by thomascountz »

thaumasiotes wrote: post #19
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…

> 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'm not arguing this point. I conceit, I thought the sentiment was obvious. If it wasn't—and if read literally—I thought that that statement was the weakest and most uninteresting part of what I shared. However, to my surprise, this statement, and its specific interpretation, is what people found compelling!

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

#132

Post by hitarpetar »

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 :).

> Hate to be the... whoever I'm being right now

the word you're looking for is pedant

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

#133

Post by matsemann »

lexicality wrote: post #11

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!

Gonna miss it. So fun to see how fast one can parse the problem, figure out how to solve it while thinking of edge cases, and then actually write and run it. I've never been high up on the leaderboard, but enjoyed waking up early in December and give it a crack. Most often rank ~1000, a few times ~100.

But I also understand the decision. Fun while it lasted, but I'll find other ways to have fun with AoC this year!

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

#134

Post by ihuman »

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 wouldn’t be surprised if the creator has metrics that show that most people drop off around the halfway mark, for the exact same reason

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

#135

Post by matsemann »

spion wrote: post #127

I wonder if it would've felt more natural if the "part 2s" of the puzzles became separate days instead. (Still 12 days worth of puzzles, but spread out across 24 days, with maybe one extra, smaller, easier puzzle for the last day to relax)

Then the 24h between part1 and part2 could be spent trying to predict what part2 will be, or generalize the solution to see if you can handle whatever part2 throws at you. For instance the lanternfish ( https://adventofcode.com/2021/day/6 ) one would expect to just have a higher number, so if one solved part1 iteratively one could make an educated guess for a fast part2 solve.

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

#137

Post by Insanity »

Although number of puzzles != time investment, selfishly I’m down for this change. As I get older it’s harder to find time to complete them, so I’m hoping this also relieves some of the (artificial) pressure to keep up with daily puzzles by decreasing the time spent per day.

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

#138

Post by mewpmewp2 »

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.

Perhaps coding exercises that require 2d or 3d thinking, or similar. This is where I have seen LLMs struggle a lot. There are probably other areas too.

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

#139

Post by toast0 »

TeMPOraL wrote: post #96
geerlingguy wrote: post #95

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!

> the Commercial Calendar is steadily squeezing the Christmas Season into December and out of the rest of the year!

We can only hope. The Christmas song containment fields are weakening as we speak.

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

#140

Post by paulcole »

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 :).

> Hate to be the…

You don’t seem to hate it that much?

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