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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

#31

Post by gf000 »

ekimekim wrote: post #9
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.

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.

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

#32

Post by HiPhish »

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 just too much time. If it was one puzzle every two days it would be more manageable.

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

#33

Post by danielbln »

matrss wrote: post #27
thaumasiotes wrote: post #19

Earlier quoted context omitted.

> 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?

IMO "Advent of Code" only determines the timeframe in which it happens, not the amount of puzzles it must contain. It could just as well be four puzzles, one for each sunday of the advent, or any other amount, as long as they are released within those roughly four weeks before christmas.

Eh, the implication has always been that it's a Christmas calendar where you open one door per day until it's Christmas eve - just with code riddles instead of chocolate.

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

#34

Post by akerl_ »

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.

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

#37

Post by ThunderSizzle »

akho wrote: post #29
thaumasiotes wrote: post #19

Earlier quoted context omitted.

> 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?

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

That would "require" a timeline shift for it to start on Christmas run until the Ephinany.

Although I don't think anyone really knows what the 12 days of Christmas are anymore.

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

#38

Post by roetlich »

danielbln wrote: post #33
matrss wrote: post #27

Earlier quoted context omitted.

IMO "Advent of Code" only determines the timeframe in which it happens, not the amount of puzzles it must contain. It could just as well be four puzzles, one for each sunday of the advent, or any other amount, as long as they are released within those roughly four weeks before christmas.

Eh, the implication has always been that it's a Christmas calendar where you open one door per day until it's Christmas eve - just with code riddles instead of chocolate.

> one door per day until it's Christmas eve

That would be 24.

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

#39

Post by gooodvibes »

No more leaderboard too!

These look like positive changes, a 2x longer event isn't 2x more fun or 2x more satisfying to participate in.

After skipping the past couple of years, I feel like I'm more likely to give it a go again this year.

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

#40

Post by klustregrif »

Really appreciate thise changes! Both the reduction in puzzles which means less work, but overall I don’t think it’s going to make the event less fun.

And removing the global leaderboard is good, rather than trying to police how people solve the puzzles just let people have fun on their own boards with people they know.

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