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
#2From FAQ: "Why did the number of days per event change? It takes a ton of my free time every year to run Advent of Code, and building the puzzles accounts for the majority of that time. After keeping a consistent schedule for ten years(!), I needed a change. The puzzles still start on December 1st so that the day numbers make sense (Day 1 = Dec 1), and puzzles come out every day (ending mid-December)."
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#3One 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.
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#4Whenever 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 nothing to do with it.
And aren't we so lucky that it isn't! Aren't we lucky to have had the prior 500+ challenges given as gifts over the years! Aren't we lucky to have a great demonstration of humility and care! Aren't we lucky to have 12 new gifts to look forward to this year!
Thank you!
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#5Tryhards 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
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#6One 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.
Agree. It was getting in the way of me spending time with the family because I was distracted mulling over the puzzles.
I had thought last year that they could peak the difficulty around the middle of the month and bring it down a bit leading up to the 25th. But just finishing it earlier is probably better IMO.
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#7One 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.
Doesn't help that the puzzles become increasingly tricky and you can't just solve them as you sip your coffee anymore (although some apparently can).
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#8Whenever 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.
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#9Whenever 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.
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.
Re: Advent of Code 2025: Number of puzzles reduce from 25 to 12 for the first time
#10Tryhards 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
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