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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

#61

Post by kleiba »

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 :).

For Christian Advent to be exactly 25 days long, that would be a coincidence.

Advent is not the time from December 1st until Christmas, it starts on whatever days the fourth Sunday before Christmas happens to fall on that year. This way, there are exactly four Sundays in advent.

If Christmas itself should fall on a Sunday one year, it doubles as the fourth Sunday of Advent, i.e., then the first of Advent will be only three weeks earlier.

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

#62

Post by kleiba »

TeMPOraL wrote: post #55
zeroCalories wrote: post #53

Earlier quoted context omitted.

Well, Christmas is cancelled this year I guess :(

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.

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

#63

Post by TeMPOraL »

kleiba wrote: post #62
TeMPOraL wrote: post #55

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.

Give a kid half of an advent calendar and tell them to open the window every second day, let's see how long it'll keep their interest (I expect much less than 12 days) :). That's not how Advent Calendars work!

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

#64

Post by sandruso »

Big AoC fan these are welcomed changes. I've always started strong but fell off as it was increasingly more difficult to solve puzzles during nighttime. And after you miss one you kinda loose the streak.

This year I'm going to combine it also with mine noaidecember challenge to get a little more dopamine from problem solving.

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

#65

Post by TeMPOraL »

kleiba wrote: post #61
TeMPOraL wrote: post #46

Earlier quoted context omitted.

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 :).

For Christian Advent to be exactly 25 days long, that would be a coincidence. Advent is not the time from December 1st until Christmas, it starts on whatever days the fourth Sunday before Christmas happens to fall on that year. This way, there are exactly four Sundays in advent. If Christmas itself should fall on a Sunday one year, it doubles as the fourth Sunday of Advent, i.e., then the first of Advent will be only…

All correct. Which is why I said religious slash commercial tradition - Advent is first and foremost just another sales event, and for convenience of sellers and buyers (and their children) the commercial advent got regularized to 25 days, so the stock of calendars that failed to sell last christmas season can be put up to sale in the coming one.

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

#66

Post by runekaagaard »

mid-kid wrote: post #56
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.

This. The best I've ever achieved is maybe 15 puzzles on one year, with gaps for the days I missed. And this was when the puzzles were incrementally building upon implementing a bytecode interpreter, which was relatively little work per day. Once I miss my first day, playing catch up is an effort in vain, as the puzzles start taking 4+ hours to solve each, solving multiple in one day is a full-time commitment. Most a…

Yeah, totally this. I've had so much fun with AoC, learning nim, elixir at the same time.

I would normally tap out around the same place on the first dynamic programming puzzle which just takes me so long to wrap my head around each time (tips anyone? :)).

I welcome these new changes, and what ever the format are very greatful for all his hard work!

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

#68

Post by kleiba »

TeMPOraL wrote: post #65
kleiba wrote: post #61

Earlier quoted context omitted.

For Christian Advent to be exactly 25 days long, that would be a coincidence. Advent is not the time from December 1st until Christmas, it starts on whatever days the fourth Sunday before Christmas happens to fall on that year. This way, there are exactly four Sundays in advent. If Christmas itself should fall on a Sunday one year, it doubles as the fourth Sunday of Advent, i.e., then the first of Advent will be only…

All correct. Which is why I said religious slash commercial tradition - Advent is first and foremost just another sales event, and for convenience of sellers and buyers ( and their children) the commercial advent got regularized to 25 days, so the stock of calendars that failed to sell last christmas season can be put up to sale in the coming one.

Agreed, I didn't mean to critique you!

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

#69

Post by TeMPOraL »

fud101 wrote: post #42
gf000 wrote: post #31

Earlier quoted context omitted.

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]

Since a "sentence", much like everything else in practice, is almost but not quite what the formal definition says, just use an LLM for this task.

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

#70

Post by TeMPOraL »

kleiba wrote: post #68
TeMPOraL wrote: post #65

Earlier quoted context omitted.

All correct. Which is why I said religious slash commercial tradition - Advent is first and foremost just another sales event, and for convenience of sellers and buyers ( and their children) the commercial advent got regularized to 25 days, so the stock of calendars that failed to sell last christmas season can be put up to sale in the coming one.

Agreed, I didn't mean to critique you!

I appreciate you working out the math above! :).

(I never could wrap my head around all this. I had enough problems with Easter events, where the math makes a detour through a Lunar calendar.)

EDIT: And my memory of the Tradition is wrong too, it's supposed to be 24 - as confirmed by https://news.ycombinator.com/item?id=45710618, and corroborated the two "Paw Patrol" themed Advent Calendars I just found still stashed in my home office.

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