advent-of-code

[woven oriole]

15

[stable heron]

10 seconds

[steel oyster]

10 secconds....

[earnest forge]

GLHF

[hazy pendant]

10s

[winter vigil]

6

[woven oriole]

5

[stable heron]

2

1

[sinful pawn]

ngl, this emoji looks too much like a thumb

[hidden copper]

<@&518565788744024082> Good morning! Day 7 is ready to be attempted. View it online now at https://adventofcode.com/2021/day/7. Good luck!

[winter vigil]

hf

[magic bridge]

well i can still attempt day 5 right and its delayed due to school

[hollow wharf]

good morning

[warm grail]

sure

[winter vigil]

seems like day 7 is a dfs min question?

[velvet stag]

49th global

peak aoc

[stable heron]

YES DONE

mafs

https://tenor.com/view/im-lost-formula-confused-calculate-gif-9919713

[iron reef]

Dammit even when I find the time to log in at reset time I'm second to the oliver ni guy

well hopefully at least I made ground on everyone else

[regal garnet]

I think I got a good solution but its gonna have to wait intil tomorrow

[signal grotto]

boom done

[ivory ravine]

rip

[sonic silo]

damn it

[winter vigil]

lol damn

that was easy

[sonic silo]

i really have the idea but im not sure how to execute it

[ivory ravine]

anyone else getting this on leaderboard pages?

[narrow crown]

nooo this one was easy i couldve done it

rip math hw

[sonic silo]

i dont understand...

[hollow wharf]

yay i made it to 3 days!

[signal grotto]

yep

[hazy pendant]

i got two stars!

[mystic plover]

yo i did part 1

[hazy pendant]

in 14 minutes :(

[marble minnow]

It's my first aoc and I am wondering if the rest of questions will be also short?

Or will we get something complex to solve

[hazy pendant]

weekends:

[quartz crest]

damn aoc is down?

[hazy pendant]

not for me?

[quartz crest]

the leaderboard pages

[uneven hollow]

today's was easy

[quartz crest]

ikr

[hazy pendant]

damn those users are f a s t

i'm envy

[uneven hollow]

persoanl leaderboard is down

[hazy pendant]

leaderboard

ah

i was looking at public leaderboard

welp time to uninstall python3.9

[summer kraken]

It was ez today..

[uneven hollow]

yeah

[summer kraken]

kind og

[uneven hollow]

i just brute forced

[summer kraken]

Hey... is the advent of code site crashed or unresponding?

[outer chasm]

Hmm that was actually alright

[hollow wharf]

i seem to have misread something in the instructions

lol

[hazy pendant]

uninstalls python3.9

installs python3.10

relief

[uneven hollow]

lol

let me install 3.10

[hazy pendant]

||the fuel, not the position||

[hollow wharf]

i was missing a +1

lol

[summer kraken]

imo many libraries don't supportit yet.

[hazy pendant]

no

[uneven hollow]

oof

[hollow wharf]

i think

we'll see

[hazy pendant]

i reject

i will install python3.10

[summer kraken]

ok..

[hazy pendant]

you can't stop me

https://tenor.com/view/kozhi-nuclear-bomb-gif-18586883

distutils.util

oh no

[mystic plover]

guys is there a cool way to do p2

wait no wrong chat

[winter vigil]

sooo lost on why this isn't working

for test in positions:
    fuel_cost_total = 0
    for pos in positions:
        steps = abs(pos-test)
        cost = sum([i for i in range(1,steps+1)])
        fuel_cost_total+=cost

    fuel_sums.append(fuel_cost_total)

print(min(fuel_sums))```

[hazy pendant]

i reinstalled pip, time to install bloat

[stable heron]

||you're just going through the different inputs||

[hazy pendant]

and yes i installed python3.10-full instead of python3.10

[stable heron]

||the most efficient horizontal position is not necessarily in the input||

[winter vigil]

yes i just noticed that

i can't read instructions lol

[topaz summit]

||what if there are multiple crabs in one position?||

[clever pecan]

this was so much easier then yesterday

[summer kraken]

It was much computer-friendly than yesterday.

[void ocean]

yeah it's an off-day

[stable heron]

which is probably why the website went down

[signal grotto]

hi, lil PSA: yes there are site issues. yes the folks behind the site are aware. yes they're looking into it. no eta or anything else right now :)

[humble copper]

difficulty is not balanced at all

[signal grotto]

but ofc as I say this they seem to come back

[humble copper]

literally easier than yesterdays, much easier than the day before that

[void ocean]

it increases in linearly on average

there are some off days to control pacing and prevent burnout

[signal grotto]

also weekends are harder on purpose

[steel oyster]

ok day 7 done

[winter vigil]

just finished too

[humble copper]

wait just for future reference

is having this happen an indication of something not being done optimally

[winter vigil]

51% cpu just from a python script

damn

[humble copper]

no its 31.3

[winter vigil]

it could mean that?

[humble copper]

51% total

[winter vigil]

oh yea read wrong

well python was taking up 90% of my memory yesterday from my list with like billions of elements

[sinful agate]

me when list(permutations(inp, len(inp)))

[covert arrow]

.aoc join

[pine tiger]

probably not lol

[velvet knot]

Thought I was done after the bingo one

But 5,6 and 7 were pretty chill

[tame kiln]

.aoc join

[earnest forge]

You never need to pass len() of the list you're passing to permutations because that's the default

[violet raft]

hello, could someone give me a hint on whats wrong with my code for lanternfish part 2

[velvet stag]

both parts are the same

if it worked for 1, it's still correct

[violet raft]

i had memory error when using same method for first part

[covert arrow]

try optimising it

[hollow wharf]

if you are ||appending to a list|| beware because ||it will end up needing terabytes of memory, aka not gonna happen|| so you likely need a new approach

[covert arrow]

yes

[covert arrow]

how do i put spoilers btw

[hollow wharf]

double ||

||or /spoiler seems to work||

[violet raft]

ok, thx i have an idea of ||memoization|| hopefully that works

[thick talon]

hi why does this

x = ['00100', '11110', '10110', '10111', '10101', '01111', '00111', '11100', '10000', '11001', '00010', '01010']

for i in x:
    print(i)
    if i[0] == '0':
        x.remove(i)
print(x)
``` output ['11110', '10110', '10111', '10101', '00111', '11100', '10000', '11001', '01010'] instead of ['11110', '10110', '10111', '10101', '11100', '10000', '11001']

this is for the binary diagnostic part 2

[eternal berry]

Hi, I had the same problem. When you remove an element from a list, each elements index shifts -1. So if i = 2, and you remove 2, the element in index 3 becomes index 2

[stable heron]

removing items from lists while iterating it

not a good idea

nu uh

[thick talon]

ohh ok

[eternal berry]

Easiest way around it that I found was to do:

for i in reversed(x):

[thick talon]

what should i do then alternatively

[stable heron]

do the removal on a copy of the list

or

hmm

[eternal berry]

We don't care about the order of the elements in this case, so reverse works well

[sinful pawn]

don't mutate lists while iterating over them, you'll run into really funky things

[thick talon]

oh why should i reverse the list

[stable heron]

i forgot how i did this one

[thick talon]

woudnt it output the same result?

[sinful pawn]

instead: y = x.filter(lambda s: s[0] != "0")

[eternal berry]

Nope. If you delete from back to front, you never shift the elements indexes. Using reversed probably isn't the best way of doing it, but it works.

[thick talon]

i dont rlly know this but im guessing filter filters out stuff based on a condition and lambda s is the condition?

[stable heron]

yes

[sinful pawn]

it passes each item into the function as s in this case

keep if true, toss if false

[thick talon]

ohh i thought you just iterate through a reversed list

[thick talon]

alright tyy

[pale heath]

at least today was easy

[sinful pawn]

LMAO I'm still stuck on day 4

I've been putting it off

I'm scared of 3D arrays

[eternal berry]

I'm having a weird issue with the same problem. Day 3 solution 2. I've worked out oxygen. Co2 is the same but the other way round, however when i'm indexing through the binary list, it gets to index 8 and I have 3 binaries left. At index 9, I have an empty list 😦

[thick talon]

you need a condition when u get to one element right?

[eternal berry]

Yeah. I have a condition, but when I get to index 9, each binary left in the list has the same bit, so they're all removed

Everything worked fine for oxygen list though, so I must have screwed up somewhere.

[stable heron]

im stuck on day 20 of aoc 2015 😔

i need to find n prime numbers such that their sum is >= x and they have the least product 😩

[thick talon]

@sinful pawn

[stable heron]

try list(filter(lambda s: ..., x))

[sinful pawn]

oops, I mixed it up

I'm used to Nim

[thick talon]

do i put filter before

the x

[sinful pawn]

huh?

[stable heron]

nono try this

[thick talon]

oh alright thanks

[eternal berry]

1 is the least common bit at index 9, so all my binaries are going to be removed from my list 😦

I'm so confused

[thick talon]

only the 2nd element is being remove tho

[eternal berry]

Why would only the second element be removed?

Ah sorry, my screenshot is misleading

[velvet stag]

yeah all should be removed, if it's second thing

[eternal berry]

so the next step in the loop is to remove all strings with a 0 at index 9, which is all strings

[velvet stag]

probably went wrong on some previous step

[eternal berry]

I don't understand how i've managed to get to this position though. My loop looks to do exactly what it's meant to do, and it worked perfectly for oxygen (or atleast I think it did)

[velvet stag]

not sure

[thick talon]

If 0 and 1 are equally common, keep values with a 1 in the position being considered.

did u take that into consideration

[velvet stag]

there's 50% chance you just got that wrong yourself

yep, it says the opposite

personally I just tried all 4 ways

got it wrong thrice

make sure you're counting left to right

[eternal berry]

So here's another screenshot to give some context:
index is the index of the binary. position is how many 1's are in each index position.

As you can see in index 9, there are 478 1's, which means 1 is the least common bit as it's < 500

Yeah it's counting left to right, i've been watching as it debugs. I may just open a new help channel at this point. It's almost as if my puzzle data is wrong 😄

[velvet stag]

?

don't compare with 500

do it normally smh

[eternal berry]

I have 1000 elements in my puzzle data, so I did (len(puzzle_data)/2) to get my threshold so to speka

[velvet stag]

yeah, that would produce wrong result

[eternal berry]

so if 1 or 0 >= (len(puzzle_data)/2), then that is the most common bit in that index position

[velvet stag]

instead get a new, less wrong threshold after you filtered the numbers on each step

[thick talon]

use the sample data first

and see if that works

[eternal berry]

Ohhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh

...

Massive oversight on my part 😄

[sonic silo]

i wonder if its possible to extract the sample quickly from the webpage

[thick talon]

did u figure it out?

[eternal berry]

I can see where i've gone massively wrong yeah 😄

[velvet stag]

there was a script that aimed to do that yeah

[thick talon]

nicee where did u get wrong?

[eternal berry]

It's how i'm figuring out my threshold. I was doing it once for the entire puzzle, rather than making it part of my loop

[winter vigil]

what day do you guys think will the first recursion heavy problem?

[thick talon]

ohh lmao

[sonic silo]

yeah that would be nice

[velvet stag]

friday

[tight dune]

oops wrong server

[peak dock]

hmm the personal stats page is still down

[jade atlas]

.aoc stats

[hidden copper]

:x: Please use #aoc-bot-commands for aoc commands instead.

[sinful pawn]

oh yay, that's a thing

[eternal berry]

Day 3 complete. That was a tough one 😄

[weak torrent]

I got O(n * log(max(arr)) solution for day 7

🙂

[sinful pawn]

god. can't believe we're on day 7 already

I still have been procrastinating day 4

[weak torrent]

day 6 was the toughest till now imo

[sinful pawn]

oh boy.

[winged trellis]

i found 4 and 5 to be harder then yesterdays

but on average weekend puzzles are harder because you have more time to do them

[weak torrent]

hmm 4 and 5 were more like simulating was they told

6 was the first time we had to optimize

[winged trellis]

True, that is the norm on average tbh

[willow ocean]

Guys, do you think there is also an analytical solution to today's challenge?

[weak torrent]

I found one, it decreased my time from 0.68 sec to 0.015 sec on python

[winged trellis]

for part 1 yes, part2 you have to guess within a very short range

my current solution is about 13 ms, but i loop over the short range

[weak torrent]

tbh I don't feel my solution will work for every possible test case

but in this format it just works

[winged trellis]

if we pooled all inputs together we could prove experimentally that the range most likely is at one index instead of +- 1

[sinful pawn]

I have a feeling there exists some massive inputs somewhere

[winged trellis]

if i remove my range where i do my educated guess, i go from 13ms to 5ms

[willow ocean]

Nice. I have a solution in NumPy and it's basically instantaneous.
Nonetheless, I'm interested in the analytical solution. Could me point to some resource?

[winged trellis]

there has been a lot of talk about it earlier in #advent-of-code-spoilers-archive

[sinful pawn]

I'm gonna try using Arraymancer for day 4

[willow ocean]

thanks

[sinful pawn]

For those wondering: https://mratsim.github.io/Arraymancer/

nvm I'm already confused

what on Earth is a tensor

[modern scarab]

a matrix with n dimensions

[sinful pawn]

I figured that out a bit later

[queen python]

Question on day 6 part 2. Is it possible to solve part 2 with 'brute force' algorithm? If yes on what machine? I guess a lot of ram? Part 1 works but part two is very slow and crashes with out of memory.

[oblique pasture]

Did The Site Go Down?

[peak dock]

yeah looks like it

[oblique pasture]

😦

[winter vigil]

use the Counter() from the collections library

the key to day 6 part 2 is realizing the redudancy in the way the fish grow over time

[peak dock]

someone calculated it would take 11 terabytes of ram for the bruteforce to work

[winter vigil]

wow

[queen python]

I see 😆

[winter vigil]

yea, they really wanted you to think outside of the box for this

when i figured out the O(n) solution, i was soo happy

realized how simple it actually was

[queen python]

Yep problems are generally difficult until they are simple 😜 i agree. This one is still hard for me lol.

[weak torrent]

is the 25th problem in aoc similar to mediums in cp?

[peak dock]

you can check out the past years' problems

[sonic silo]

the last day tends to be much easier than its previous days

at least the first part

the second part... well

that depends on how well you did

[weak torrent]

oh

[mossy basin]

2019 day 25 i managed to solve the puzzle adventure thing really fast by pure luck

oh i even globaled

finished 44th on day 25

[sinful pawn]

lord I hate day 4

[winter vigil]

Day 4 is the bingo one?

I still need to do part 2 of that

[sinful pawn]

omg finally

[rapid wolf]

Gj

Not mine afaik

[fossil cipher]

I hate these kind of AoC puzzles. I managed Part 1 on my own, more out of dumb luck than anything. Part 2 I had to borrow ideas. Still no idea how it works.

[wary veldt]

What kind of Aoc puzzles? day 7?

I used brute force for day 7 and it took less than 2 seconds in python

[fossil cipher]

Yeah. Maths/Stats is not my strong point. I did consider just brute forcing it but I feel like that's my solution to everything in AoC when I barely understand what's going on 😄

[wary veldt]

hopefully it gets more interesting soon, I was kinda disappointed and surprised when my brute force solution not only worked but was so quick even with a 'slow' programming language

[fossil cipher]

Day 6 was fun.

Part2 - 256 days

Easy!

fans go to Orbital Launch Speed

hmm...

Very pleased with myself when I realised what the better way was 😄

[bright spindle]

I went straight for binary search, it didn't even occur to me to bruteforce it.

[hollow wharf]

is there any way I can post a PDF? I wrote a whole-ass paper explaining why the mean kinda works for part 2, and I think it's pretty nifty

[bright spindle]

I don't think so? I guess you can put it somewhere and link to it.

[hollow wharf]

this is so sad

[fossil cipher]

I hope the paper is titled Whole-Ass Paper on Why the Mean Kinda Works.

[loud yew]

my solution for part 2 took 1:24 to run .-.

[fossil cipher]

or Why the Mean Kinda Works - A Whole-Ass Paper

[bright spindle]

Do What I Mean, Not What I Say

[hollow wharf]

It's called "On the Unreasonable Efficacy of the Mean in Minimizing the Fuel Expenditure of Crab Submarines"

[fossil cipher]

Wait for the day that shows up as a citation in a statistics paper somewhere 😄

[hollow wharf]

that's the goal

[fossil cipher]

I'm not in academia, but I heard somewhere recently that any scientific/mathematical paper that has a question in its title, the TLDR is "No".

Is that true? 😄

[hollow wharf]

I cannot speak to that sorry

I'm trying to put this damn thing on my website and it refuses to work for some reason

[hollow wharf]

it's in #advent-of-code-spoilers-archive in png form

[humble escarp]

Done 😄

[fossil cipher]

https://tenor.com/view/jeff-goldblum-crazy-son-of-a-bitch-you-did-it-jurrasic-park-gif-19484615

[hollow wharf]

It's on https://www.reddit.com/r/adventofcode/comments/rawxad/2021_day_7_part_2_i_wrote_a_paper_on_todays/

[sinful pawn]

omg my answer matches the sample

now, one prays

fuck. lol

what'd I do this time

[hidden musk]

does this input look like intcode or...

should I actually read the problem instead of just looking at the input

[sinful pawn]

well... this ain't good

I keep getting an answer as 0

[sonic silo]

SAME

that happened a lot and im not even sure why

it delayed me for 20 minutes unnecesarily

[sinful pawn]

I've also come to realize that kitty is very annoying to work with

the scrollback buffer does not get cleared with the rest of the terminal

I thought I was scrolling through like an infinitely long error, but it was just a concatenation of all my past errors

[loud yew]

ssshhhhhhhh

[verbal rampart]

.aoc join

[sinful pawn]

I wanted to get this down hours ago

I'm so confused

this should be impossible...

this is driving me insane... How on Earth is this even possible

the entire board gets filled up without triggering a win until the very last number

[bright spindle]

https://tenor.com/view/thats-impossible-star-wars-luke-skywalker-no-gif-17196576

[sinful pawn]

... but I cannot replicate for the sample input meaning I have no idea of figuring out what edge case I didn't account for

it literally works perfectly for the sample

[bright spindle]

@sinful pawn Debug and step through the code line by line until it does something you didn't expect.

[sinful pawn]

I've been doing this for like the past hour ;-;

[bright spindle]

Post your code in #advent-of-code-spoilers-archive

[sleek cave]

sees problem
wait, isn't this that familiar math problem I solved a few days ago
realizes I brute forced that problem
oh.

[sinful pawn]

welp... I've gotten an answer other than 0

here's to more praying

[craggy wraith]

i guess Rust is saving us from Docker in this challenge

[sinful pawn]

praise the lord

I feel a lot less proud of myself than I should

[sleek cave]

i feel like starting from day 6 the challenge isn't just programming the solution anymore, nothing is straightforward and you need to actually have a good algo to solve

woohoo, algorithms, the number one thing I'm not experienced with

[sinful pawn]

this too so long, man

5 hours!? Surely I procrastinated for most of that

[sleek cave]

lol, took me 3 minutes for day 6 part 1 and 3 hours straight for day 6 part 2

[sinful pawn]

I'm on day 4 😔

well... actually... I can finally say that I was on day 4

[sleek cave]

day 5 now, WOOOOO

[sinful pawn]

😔

my brain is fried

[sleek cave]

🎉🎉🎉🎉

[sinful pawn]

I don't even wanna look at day 5 or 6

I hear people saying that 6 is tough 😔

[fossil cipher]

Day 5 and 6 aren't too bad

[sinful pawn]

yeah and people said day 4 was easy peasy

[sleek cave]

same for day 6 lmao, I asked for two light hints because I coded for 2 hours without progress

[sinful pawn]

but here i am

[fossil cipher]

day 6 is mostly a case of "what the hell... how..." then easy peasy if you realise the best method 😄

[sinful pawn]

shame

I've got a headache

[sleek cave]

day 6 is easy if you have experience with a certain programming concept
ofc, if you're like me and you don't... expect hours of fun

[sinful pawn]

please tell me that day 5 and 6 aren't anything to do with nested sequences

[sleek cave]

5 kinda

[sinful pawn]

oh no

[fossil cipher]

day 6 is just a list

[sinful pawn]

I... hate trying to comprehend "board" logic

and whatever the heck tensors are was a mistake

[fossil cipher]

only one "board" on Day 5 😄

[sinful pawn]

oh no

[sleek cave]

||one xy coord system on day 5, that's it||

[sonic silo]

tbh

these days arent too bad, you should take it easy and try to subdivide the problem into simpler parts and youll eventually be capable of assembling a proper solution

[sleek cave]

this.

[craggy wraith]

i had 11 for loops in my code for that problem

[sinful pawn]

My problem was that the sample input was too short for me to accurately test

I also actually accidentally did part 1 wrong

I forgot to consider columns

I only checked rows

[woven sable]

Day 7 isn't as bad as I expected it to be

[bright spindle]

Why did you expect it to be bad?

[woven sable]

Hmm, considering we're a week into AOC

Is it easier because it's a weekday?

[bright spindle]

I find that aside from a few outliers, most AoC problems don't really get significantly harder as you go.

There isn't much of a difficulty progression.

[fossil cipher]

I think it's more your own knowledge that dictates the difficulty. If you fail to spot the pattern or class of problem, you're doomed to struggle.

[wooden jewel]

Didn't they have you write interpreters and shit previous years? Day 7 - 2020 looks significantly harder than day 7 this year at least

[sonic silo]

IMO, while the difficulty trend does absolutely exist, i dont think that affects as much as ^

[sonic silo]

||day 7 is just day 6|| in some ways

in that you needed ||recursive memoization||

(iirc)

[bright spindle]

2019 was the intcode year, I think

But it wasn't as bad as all that

[sonic silo]

IMO 2019's problem was just the fact that an early puzzle was required in order to solve a latter puzzle

so if you couldnt for any given reason resolve day 2, you couldnt resolve the rest of like. 10 puzzles dedicated to intcode

[fossil cipher]

I quite liked the intcode puzzles, but yeah - if you failed to solve an intermediate step it kinda sucks

[sonic silo]

otherwise interpreted puzzles are neat

i actually really love aoc 2019 and how creative it got with a lot of its puzzles, its such a shame its so infamous lol

[fossil cipher]

I should revisit it. I recall one puzzle where you had to link up several instances of the program. I solved it by hacking together a bunch of generators. Be interesting to see if I learned anything since then.

Prediction: I probably haven't 😄

[craggy wraith]

my code probably wasn't the best for time complexity, but it still worked

it just took like 3-4 mins to run though

[wooden jewel]

(I didn't participate in 2019, but might try at a later time)

[fossil cipher]

I think generally weekend puzzles are more difficult or at least require a bit more finesse.

[craggy wraith]

i want to try complete some of the previous years, which ones would you suggest to start with

[sonic silo]

any of em, hell you might as well pick and choose puzzles from different years

[mossy basin]

i did the same, but i'm pretty sure i would just write it async now

[fossil cipher]

Might be an excuse to really dig into async. I suspect it will be beneficial to me in at least one project at work I want to start at some point.

[mossy basin]

i recommend "Build your own async" by beazley

[woven sable]

Beazley has so many great talks

[woven sable]

.bm talk

[fossil cipher]

I'll have to check that out. Cheers

[mossy basin]

https://www.youtube.com/watch?v=Y4Gt3Xjd7G8

[woven sable]

oh

I should bm that

[mossy basin]

can just bookmark that

[woven sable]

.bm link

[sinful pawn]

bad manners

[hollow wharf]

is there a way to make today's first part without bruteforce?

[hidden musk]

yes

[hollow wharf]

@peak dock haven't done the challenge first 🙈

so there is

hmm

right

[peak dock]

oop

[hollow wharf]

alright, surely there is no none bruteforce solution for the second part, right?

or should I keep thinking

(something reasonable, no like crazy linear algebra with matrix exponentials and whatnot)

[tight dune]

i bruteforced the 2nd solution if u mean the 7th day

[hollow wharf]

yes

I mean bruteforcing is the obvious solution but is there a better one

[tight dune]

i have been wondering the same thing

heck, is there a better algo for part 1 itself

i bruteforced part 1 too

[woven sable]

So basically a solution that isn't O(n^2)?

[tight dune]

i guess

[hollow wharf]

yes

part 1 can be O(n)

O(1) in finding the right end position

[woven sable]

Wait how?

Like out of curiosity

[tight dune]

WAIT

#advent-of-code-spoilers-archive

[woven sable]

Oh yeah

[hollow wharf]

||The most optimal solution is the median of all the input||

assuming linear cost

[tight dune]

oh i was trying mode, weighted mode, etc

then i gave up and brute forced it

[rancid mural]

I remembered a story my math teacher told me about Blaise Pascal solving part of this problem, but googling it just returned Pascal language implementations of something else

[hollow wharf]

0.33s, good enough

lru cache is such a beast

[eternal berry]

Does anybody know a time-efficient way of getting the day4 puzzle into some data structures?

[mossy basin]

is that bingo

[eternal berry]

it sure is

[hollow wharf]

ooh

O(log n) should be feasible

[mossy basin]

i used re utility combined with numpy

but, you can easily get boards without that

[bright spindle]

||I found the optimal position with binary search, so that's O(log(m)*n)||

[mossy basin]

oops, this is not spoilers channel

[tight dune]

[eternal berry]

😄

[mossy basin]

my bad

[final eagle]

aight i am out all day

whats today's aoc

how hard is it*

[peak dock]

not too bad

[eternal berry]

can i ask, is getting the puzzle data into data structures meant to be coded also? i'm on day 4 and i've just manually put a bingo board into a list of lists and I don't think it's really feasible to go through each board and wrap them in brackets and add comma's etc. Should i look to code this? I had a look at numpy but that looks to expect data in a comma delimited list format.

[hearty shuttle]

Definitely code it up

As a suggestion, think of splitting the whole string into the boards piece by piece. Think either normal string split or regex to split

[final eagle]

yep did it in 8 minutes, seems to be the second easiest i have done

[hearty shuttle]

If it helps, my approach is to always take the whole string as input, and then decide how to parse it

It depends day to day how the parsing goes

[eternal berry]

Hmm okay. I think this may be a bit advanced for me but i'm going to give it a shot 😄

[mossy basin]

when i first read the problem i thought it would be difficult, but i did get the answer in roughly 5 minutes for both parts

[jade root]

lmao i am 69th place

[final eagle]

i have given up on trying to get a good placing on the leaderboards

[jade root]

lol same

[final eagle]

cant really arrange my schedule to fit aoc in haha

now i am just doing it for fun

[jade root]

thats the most important thing :)

[final eagle]

interestingly still 122, wonder what will it be after the board updates

oh, rose to 44

[hollow wharf]

interesting, the design of https://adventofcode.com/ and https://adventofcode.com/2021 isn't the same

[bright spindle]

It's good practice, parsing data is very common in all kinds of contexts in programming in general.

[tight dune]

👀

what does this mean

[hollow wharf]

good question

[rapid wolf]

the characters are randomized

[hollow wharf]

oh lol

[hollow oyster]

how can I even write code for aoc, I never went that far

[hidden musk]

how are you solving the problems?

[hollow oyster]

I never went that far

[thick talon]

how do u get all the elements that are in the same column in a list

[peak dock]

transpose it with list(zip(*A)) and index into it with the column #

[steep shard]

wat

[hollow oyster]

what?

[steep shard]

what do u mean "how to write code for aoc"

[hollow oyster]

don't question me I did not know how aoc works

now I know

[steep shard]

o

lol

[native crystal]

Is everyone busy trying to solve advent-of-code??

[steep shard]

is todays challenge like yesterdays

where u need to find a efficient method

[rotund rapids]

I mean this one feels kinda brute forcible, but an efficient method is nice

[steep shard]

kk ty

[eternal berry]

Hi all. I don't want to cheat and look at spoilers, but i'm struggling with parsing the data in day 4. I know exactly how I want it to look, and I think I know how to solve the puzzle once the data is parsed, I just don't know how to parse the data!

Would anybody be able to link me to some reading / a video that might point me along the right lines?

Thanks.

[bleak sable]

Nah. Because the length of input is fairly short and you don't have to iterate it multiple times. Brute force is short to write as well if you use comprehensions in builtins :3

[unique osprey]

Is that the vector one? nvm it's bingo

[unique osprey]

What are you doing right now to parse?

[eternal berry]

Il pop a spoiler tag on this just so I don’t give anything away.

[bleak sable]

||After you separate number chain and boards, one board takes 6 lines (5 lines of numbers and one empty line)

Taking 6 elements from iterable can be done like this:||
||res = [my_list[i:i+6] for i in range(len(my_list))]
You will still have to parse those 6 lines into how you want to store your board, of course||

[eternal berry]

Sorry, just wrote out my entire plan on my phone and managed to lose it all haha. Just going to grab some food but will reply when I get back

[bleak sable]

Also, I don't think there are active spoilers of day 4 now in spoilers channel, so we can go there to comfortably debug your code :3

[eternal berry]

I'll bob over to the spoilers section and write my plan down

[robust heart]

I'm reading some of the problems and I was wondering what went through their heads with the scenario

[real pine]

Lots of lanternfish

[heavy oxide]

almost finished day two 😅 how r u guys doing

[eternal berry]

Struggling on day 4 but it's definitely a good learning experience

[heavy oxide]

exactly

i am switching from c++

started learning python on monday

still struggling with basic errors

🥲🙃

[sleek cave]

uh oh, why do i sense maze-solving puzzle in the following days

[rapid wolf]

prolog time

[loud yew]

oh yeah... c r u d

[sonic silo]

good thing college made me revise search path algorithms

[sleek cave]

what's prolog?

[rapid wolf]

a programming language

one that has dfs builtin as a language feature

and makes it pretty easy to switch it to bfs

[sleek cave]

oooh nice

[mossy stream]

uh oh, maze solving is gonna be an interesting one

me who always wanted to implement A*

even if I know ali is gonna end up doing the challenge

[woven solar]

A* 🥴

[rapid wolf]

this could be a cool clash of code, alternate in moving and placing a maze, whoever reaches the goal first wins

[woven solar]

I think there's literally a codingame bot programming task similar to that

[hollow wharf]

oh god why did I post a math thing of Reddit

now I have to put up with people telling me I'm dumb in the comments

[low condor]

Most people seem to like it, and you got 500 upvotes!

You'll always get people calling you dumb when you put something up. Tis a fact of the internet

[hollow wharf]

I am learning python and C++ simutenoalsy

Or however the fuck you pronunce it

[hidden musk]

why?

[sleek cave]

isn't that one of the rules in "rules of the internet" lol

adventofrealizingimstillextremelyinexperiencedatproblemsolving.com

sigh i'm struggling at day 7 part 1, i don't want to brute force it but i may have to

[low condor]

all you have to do is work towards the answer - anyway you can

if it works it works

you can always look up if there was a more efficient way later

[wooden jewel]

Also brute force isn't too inefficient today

It isn't like the fishes one where you needed a million billion gigs of memory

[sleek cave]

still O(n^2) 😔 i reckon there's definitely a O(n) sol

you leave me with no choice, eric

the brute is here.

[wooden jewel]

there is indeed :P

[sleek cave]

lol, cheesed it with brute force, got them stars :p
gonna start working on a faster sol when i have time, i still have homework from school to do 😔

[low condor]

It ain't cheese if it works

[sleek cave]

agreed lol

[torpid karma]

Ye, I feel like most of the solutions should use brute force because it leads to more coding and less math XD.

[winter vigil]

advent of math

lol

[sleek cave]

this gives me "coding is for automation" vibes

why find an elegant solution when you can automate trial-and-error

@hollow wharf i was browsing r/aoc when i saw your paper, absolute masterpiece

sadly, i can't read it because i'm still attempting to create an elegant solution

[hollow wharf]

thank you!

[sleek cave]

lol others have the same prediction

[pine tiger]

yo what

[rancid creek]

different leaderboards with different number of players

[minor cave]

If you complete the earlier days much faster than the other person, and otherwise you're close, you'll be put ahead on boards with more players that complete the earlier days because it earns you more points

[topaz summit]

@warm monolith let's not post random inappropriate videos

[winter vigil]

please dont

[warm monolith]

I will post those videos in here.

[winter vigil]

is there a memes channel?

[topaz summit]

!ban 300234897241669642 troll

[marsh current]

:incoming_envelope: :ok_hand: applied ban to @warm monolith permanently.

[topaz summit]

there is not

[winter vigil]

:((

#python-memes

[sleek cave]

 1)  489   463 |  54.33%  51.44%
 2)  448   437 |  49.78%  48.56%
 3)  414   358 |  46.00%  39.78%
 4)  314   296 |  34.89%  32.89%
 5)  281   274 |  31.22%  30.44%
 6)  278   263 |  30.89%  29.22%
 7)  254   246 |  28.22%  27.33%
```📉

[hollow wharf]

some interesting math discussion later I have discovered that there exists a closed-form analytic solution to Day 6

It's quite ugly, but it does exist

huh it would appear that my attempt at writing a paper about the math behind day 7 has very much angered someone. this is unfortunate.

[minor cave]

haters gonna hate

[bright haven]

who is angry?

[hollow wharf]

Trying to share things on the internet sucks. I just wanted to do fun math, now someone is mad at me over some lack of rigour in my analysis

[hollow wharf]

someone from another programming server. I'm just going to ask them to write and post their own paper if they care to dispute what I've done. I'm fine with someone coming up with a different result, but they've just been attaching a "this isn't right" comment to like half the comments in the thread

I don't even know if it is right at this point, but the notifications are exhausting

Like, it turns out that the validity of criticism has no bearing on how exhausting it is to take

[bright haven]

yes, true.

ignore that guy.

[hollow wharf]

yeah just a new thing for me. not very online so I'm not used to stuff like that

[hidden musk]

unfortunate that it's such an expected thing 😔

[hollow wharf]

it's just tiring. i just wanted to share some cool math

I was thinking about writing another short paper about how day 6 is closely connected to ||circulant matrices|| but I don't really feel like it after this

[placid lake]

woah, you the one who wrote it? that was a nice little read; good job!

[sharp panther]

Would you be willing to share that paper here? I'd love to take a read.

[placid lake]

i'm sorry to hear this though. fwiw, i enjoyed reading through the paper

[sharp panther]

or perhaps in #advent-of-code-spoilers-archive if it contains specific details

[hollow wharf]

It's on the subreddit. tried posting it here, but PyDisc yells at you if you try to post a PDF

[hollow wharf]

thanks, that means a lot

[hidden musk]

plethora

[placid lake]

you can DM it to me, and i can post it here if you'd like

[hollow wharf]

sure, will do

[placid lake]

@hollow wharf' paper on day 7 part 2

[rancid creek]

ok, starting day8 now, wish me luck on guessing the problem!

(mostly kidding)

[sharp panther]

I don't really understand some of the equations, but great paper CrashAndSideburns!

[peak dock]

"mostly" 👀

[mossy basin]

1000 seconds to go!

[humble copper]

9 minutes

here we gooo

[sinful agate]

lol

[dim sphinx]

how long did it take for y'all to process part 2 of day 6, its been 15+ minutes for me so far, just wondering?

[hollow wharf]

I have a lab report due at midnight worth 16% of my final mark I’m so stressed

[hollow wharf]

About 100ms

[woven oriole]

refactor code

[humble copper]

process as in understand? or just run

[dim sphinx]

run

[humble copper]

oh

there might be something wrong with your code

[woven oriole]

it will take 16 TB ram for the naive code to compile

[humble copper]

for me its (almost) instant

[woven oriole]

for part 2

[hollow wharf]

All days have a solution which will run in under 15 seconds

[dim sphinx]

yeah, mine isnt optimized at all, but i know it works, cause i got part 1

[woven oriole]

most of the people fell into the part 2 trap of day 6

[humble copper]

mmmmmmm thats not a good practice to have in the long run

[hollow wharf]

You will need to optimise it or it will probably take several hours to days

[humble copper]

input might be so large+complex that it just wont run in a reasonable time

[dim sphinx]

i guess il do that then, thx

[hollow wharf]

I think people worked out that unoptimised day 6 takes on the order of hours to days

Not sure tho

[sick fern]

wdym trap?

[peak dock]

yea its the memory which is the bigger problem

[sick fern]

oh, that

[mossy basin]

i feel like memory and number of list operations

[sick fern]

yeah ig

anyone got better algorithm for day 7 part 2 tho?

I don't like bruteforcing

[sinful agate]

lol pain

[humble copper]

||too much list comprehension is what got mine to work||

but that seems to be a recurring pattern for me

[mossy basin]

take the derivative of the cost function and set it to zero and solve for x!

[hollow wharf]

@sick fern check this out

[sick fern]

hmmm I haven't learn about calculus yet

damn

[hollow wharf]

Ah might be hard to understand if you don’t know calculus

[bright spindle]

Besides the mean method, you can also use binary search or gradient descent to find the optimal position.

[sick fern]

binary search?

[mossy basin]

gradient descent is how you learn that mean is optimal

[north silo]

Who is ready for day 8?

[peak dock]

aye aye captain

[sick fern]

ye

[winter vigil]

is day 8 gonna have recursion i wonder

[bright spindle]

https://en.wikipedia.org/wiki/Binary_search_algorithm

[hollow wharf]

Binary search and gradient descent rely on the fact that ||the fuel function is parabolic, so the minimum is guaranteed to be global||

[winter vigil]

@hollow wharf yo whats up

[hollow wharf]

Well no not really

[sick fern]

yes ik what binary search is

[narrow crown]

ooh aoc in a minute

[sick fern]

I'm asking how is it used

[narrow crown]

✨ still havent even seen day 5 ✨

[sick fern]

in the algorithm

[hollow wharf]

This damn lab report that I need to finish aaaaaaaa

[humble copper]

you'll get there

i believe in you

[winter vigil]

why did you leave cpsc server

[humble copper]

👍

[woven oriole]

SHEEESH

[quaint hare]

I woke up just for AOC

[stable heron]

nice

30 seconds

[prisma sundial]

another day another chall

[stable heron]

20

[hollow wharf]

Which ‘un?

[mossy basin]

countdown in my terminal is leading the browser countdown

[winter vigil]

210

[woven oriole]

gl guys

[quaint hare]

it still isn't released

[hazy pendant]

3s

[hidden copper]

<@&518565788744024082> Good morning! Day 8 is ready to be attempted. View it online now at https://adventofcode.com/2021/day/8. Good luck!

[hazy pendant]

nOow

[sinful pawn]

not again

[quaint hare]

what?

[hollow wharf]

Didn’t have any interest in talking more about that course lol. Hated it.

Just nothing I wanted to talk about there

[winter vigil]

lol i see

[signal grotto]

lot of reading today, gl all

[quaint hare]

my calendar shows it's 1 hour left

oh ok refreshed it

[sinful agate]

ugh

[digital ember]

holy that big wall of text

and you get nothing out of it

lol

[hazy pendant]

i don't understand

[quaint hare]

lots of reading

[sinful agate]

lmao ikr

[steel oyster]

idk what to do

but it looks hard

[sonic silo]

hmm

[hollow wharf]

Oh god I’m not doing this tonight

[narrow crown]

it is kinda hard tbh

gonna do it in a few yrs

wish me luck

[sinful agate]

I will just go prepare for my exam smh

[quaint hare]

it's gonna be interesting

[steel oyster]

ill do it later, need to refresh

[quaint hare]

why are people just leaving

[stable heron]

so much reading

[sinful agate]

not leaving doing later

[hazy pendant]

i have IPython, why am i using regular Python

[hollow wharf]

I have a lab report I need to finish. Will attempt this once that’s submitted

[sonic silo]

this is like

the first puzzle that's actually hard to read

[signal grotto]

part 1 is really easy if you skip most of it and go read the very end

rank 598 on global 😎

[tight dune]

i didnt understand part 1

[somber plover]

how do you do part 1

[quaint hare]

how do you do any part

[tight dune]

nvm i got it

[quaint hare]

I should just read more

[hazy pendant]

so this is what i get for forgetting vimtutor 😡

[sick fern]

ye easy

[signal grotto]

read less, the very first and very last parts are easiest

[sonic silo]

wtf

my answer worked

[regal garnet]

My brain stopped processing info after 2 lines, will be back tomorrow xd

[sonic silo]

dead, dead as hell

[quaint hare]

dumb paragraph you get anything from it at end

[signal grotto]

I think I'm leaving at part 1 for now, good luck y'all

only 31 people globally have part 2 so far

[sinful agate]

bruh I got 1 as answer smh

how so bad

[pearl needle]

part 2 is difficult damn

[signal grotto]

just a bit

[sinful agate]

I keep getting 1 :(

[modern harness]

My part 1 solution was effectively a part 2 solution... Managed to get on the global leader board for the first time this season

[stable heron]

LUCKY

[fluid pebble]

what is aoc asking

i dont understand

[stable heron]

i still dont get what to do lmfao

[fluid pebble]

yeah

@modern harness please tell us

[sinful agate]

I am so dumb....

[pine tiger]

honestly

crap problem today

just brute force

[sinful agate]

wth is part 2

[quaint hare]

part 1 worked for me

[modern harness]

Its a little hard to explain... I think the best explanation is probably when they walk through the individual examples of how to go about it

[quaint hare]

I mean there wasn't any error, worked at first try. it's that easy Q today

[fluid pebble]

could you try your best

plz

[sick fern]

basically each segment is a letter

you don't know which

[quaint hare]

part 2 is the real question

[sick fern]

what you know is that some number is formed using these segments

you don't know which numbers either

[quaint hare]

did you do part 1

[sick fern]

you have to find out which segment is which

[sick fern]

yeah

done

[quaint hare]

you have read

[sick fern]

I'm out for lunch before doing part 2 .-.

[modern harness]

A clock digit has 8 segments, right? Suppose you I labeled them all a-g and told you which ones were lit up... except my labels are all jumbled up, maybe my top segment is d

[sick fern]

might have thought of smth

[sinful agate]

I followed Ben's advice

[modern harness]

If I said agb then you KNOW that is the 7 just by the fact that 7 is the only one that has 3 segments

[digital ember]

but 6 and 9 have same number of segmetns

[modern harness]

Right, but if you already identified 7, then 9 will have ALL of the 7 digits, but 6 won't.

[digital ember]

uh and if you didn't

[modern harness]

You use other logic like that. You use what you have identified

[digital ember]

ah ok, i think i get it

thanks

[fluid pebble]

ok

and...

[quaint hare]

then do

from bank import psymoney

part 2 isn't getting in my head

I'll read more

[warm grail]

did you understand what a seven segment display is?

https://en.wikipedia.org/wiki/Seven-segment_display

[modern harness]

I've explained the problem... I'm not going to explain the approach for solving it in this chat room, you'll have to go to the spoilers chat for further hints

[winter vigil]

wait, do you need to use string permutations for part 1?

[signal grotto]

answering in #advent-of-code-spoilers-archive

@warm grail

[narrow crown]

what in the world-

[digital ember]

rank 569 less go

thanks avongard :D

@woven sable looks like the test scraper failed today 😔

[late frigate]

Damn today was one interesting day

[onyx plank]

For the people who don't know what the problem is asking:
Seven segment displays work by having seven lights on a display to show a number. Google "Seven segment display" if you don't know what this is. The way it works in this puzzle are rather by having a letter represent one segment of each display. For example, I can have a represent the top line of the display. However, in this problem, each segment of the display is assigned a letter at random. You are given a list of lines where each line is a decode string followed by a data string, split with a pipe. Each line looks like this: decode | data. The decode portion contains the way to display every single digit 1-9. Because the letters are random, you don't know which letters will be used to display 1, 2, 3, etc. Additionally, the entire setup changes each line in the input, so you will need to decode each line separately. Once you decode a line, you use what you learned decoding to figure out what the actual numbers in the data portion represent.

---

Part 1
To display the number 1, a display will always illuminate 2 and only 2 sections, meaning that if your segment says dg, you know that's a 1, irrespective of which segments d or g go to on their own, as that's not important right now, you only need to know that that combination of letters in that line displays a 1. The number 4 also has a unique number of segments it illuminates, as does 7, as does 8. Find out how many segments are used in 1, 4, 7 or 8. Then, with that knowledge, find out how many times those numbers appear in the data portion of the input and that's your answer.

Part 2
Now you need to decode each line. Figure out which letter goes to which segment on the display. With that information, you'll be able to know exactly what combination of letters equals what number for that line. Using those decoded signals, figure out what the 4 digit number in the data section is. Sum up all the values in all the data lines and that's your answer.

[stable heron]

gosh this is tough asf

[humble copper]

ok this one is tricky

but im almost done

[onyx plank]

yeah as a newbie i'm just thinking on where to start and how i wanna do it, if I want to attach letters to segments, segments to letters, true falses for each letter, etc....

[humble copper]

ok im nearly there

will continue tomorrow

[void ocean]

entire setup changes each line?

meaning that each line is independent?

the wire/segment connections are different each line?

[limber needle]

yes

[void ocean]

ok thanks

[sick fern]

ye done

shouldn't have gone for lunch

[onyx plank]

I have a question: I'm currently trying to layout a method of doing this and I have a problem: If I have a list where one element is true, is it possible to find out which element is true and where it is in the list?

[sick fern]

yes just run through it

for loop

[onyx plank]

with an iterator gotcha

ty!

[topaz summit]

[e for e in mylist if e][0]

[onyx plank]

wow that's a very nice one line solution actually, ty

that's def going in the "save for later" file

[void ocean]

I'm guessing number 2 is number 1 but for hard digits as well?

[trail flare]

yea

[void ocean]

Alright, then investing time into doing the hard nums

[hazy pendant]

wait

aren't weekends supposed to be harder than others 😳

[sick fern]

why would they be

[void ocean]

because more people are available on weekends

[onyx plank]

idk man so far this is the hardest one by far

[stable heron]

idts..?

[void ocean]

oh hold up nevermind

[woven oriole]

smh

[dark slate]

really liked today's puzzle

[void ocean]

but the example input is contradictory

it says that a/b corresponds to c/f but theres a signal that's just cefabd

contains chars abcf

oh hold up i'm just confused lol

[stable heron]

lmao

one signal corresponds to one unique segment

[void ocean]

yep

[onyx plank]

abcdefg are standard for decoding a 7 segment, but the lines given to you are scrambled

[devout tusk]

Could someone explain part 2? How did they end up deducing 5353?!

[spiral copper]

your last underline is a different example

specifically the longer example they give above

[pearl needle]

the one-liner example and the larger example with several lines are different, yeah

[onyx plank]

this is a toughy

imma do this tmrw

[clever pecan]

today's was very manual, yet rewarding

ultimately a lot of fun

[sinful pawn]

this reminds me of last years

[winter vigil]

man what even is part 2

does anyone have hints?

[steel oyster]

I (still) don't understand the problem

[winter vigil]

ik that you need to work off the arrangments of 1,4,7,8

to find the other digits

but the fact that its a unique signal pattern per line troubles me

[dark slate]

think about the segments that comprise each number, how many of them there are and how you can determine that a pattern corresponds to a certain digit out of all the digits that share the same number of segments

[void ocean]

is part 2 finding the segment each signal pattern corresponds to?

instead of just the easy patterns which have unique lengths

because if it's not i'm spending time solving something i don't need to

[clever pecan]

do we give hints in this channel or in the #advent-of-code-spoilers-archive

[winter vigil]

spoilers

i mean, you could just add a spoiler to your msg

but idk if that slides

[rancid mural]

AAAAAAAAAAAA im dead

[winter vigil]

not sure how popular this opinion is: but today's part 2 is certainly harder than day 6 part 2

[clever pecan]

absolutely

[void ocean]

no one's arguing with you on that one

what's the output format for part 1?

comma-separated for each digit or

a sum?

[clever pecan]

just a number

[dark slate]

I'd say it was complex, but not hard
for day 6 I needed hints, now I figured it out on my own
it really felt like a puzzle

[winter vigil]

day 6 part 2 was soo easy when i understood how Counters worked

the collections lib is soo useful for aoc

i struggled hard last year, cuz i never made use of it

[dark slate]

I spent more time on day 6 than today

but I understand if some feel today was hard

[winter vigil]

half the battle is reading instructions

kekl

[sleek lark]

First time a learn a new feature if python. TIL sets

[sick fern]

kekw

damn literally lost and couldn't find aoc channel

[sleek lark]

Maybe I am a bit too manual but I still haven't find a legitimate use for collection.

[clever pecan]

defaultdict?

[void ocean]

I know how to deduct for part 2 but idk how to put it in code

grr

[winter vigil]

defaultdict and Counter is useful

[woven oriole]

vscode hover text during part 2 be like

[iron reef]

dammit still not gaining ground

i need these to be harder so more people above me actually drop out of some days

[wary veldt]

I don't think I've solved part 2 optimally

the solution is too inelegant to feel like it's the best one

[stable heron]

lmao

[stable heron]

same

[wary veldt]

I wrote a general solution that could work for any LED arrangement but that was most definitely not a good idea here

[sinful pawn]

y'all ever accidentally solve a part

[wary veldt]

not yet

[sinful pawn]

when your "solution" was fundamentally incorrect but somehow still ended up with the right answer

[wary veldt]

not yet

[sleek lark]

@iron reef Really ? Today I had time to wake up, commute, take coffee like any other day and I still gain 10 000 places.

Oh, I just found out that the year on the website always change format. Nice.

[void ocean]

I now know how to solve part 2 but it's less elegant than the solution I was working on

[iron reef]

there aren't even 10000 places on the discord's leaderboard

[sleek lark]

@iron reef I thought about the general leaderboard, sorry

[iron reef]

if we're talking about general leaderboard there's so many people you could go up a few thousand by starting one day at hour 23 then doing the next two at reset

[winged trellis]

can someone explain todays puzzle? i dont understand what to do or how my input works

[final eagle]

part 1 or 2

[winged trellis]

part1

[sleek lark]

Is there only like 120 poeple on the Discord's leaderboard ?

[sinful pawn]

see .aoc lb in #bot-commands

oops, in #aoc-bot-commands

I just noticed something about the aoc lb command lol

Here's our current top 10 (and your personal stats compared to the top 10)!
Proceeds to only show you only the top 9 + you

[proud cosmos]

In the output values, how many times do digits 1, 4, 7, or 8 appear?

• Because the digits 1, 4, 7, and 8 each use a unique number of segments, you should be able to tell which combinations of signals correspond to those digits.

The string of letters are a direct representation of lit up segmets on the 7 segment as it says earlier in the day

[final eagle]

be cfbegad cbdgef fgaecd cgeb fdcge agebfd fecdb fabcd edb | fdgacbe cefdb cefbgd gcbe
left of | is signal patterns, right of | is the final output
the so called "signal patterns" is what segments the submarine tries to light up when displaying a number. every line in your input has a different pattern. for example, in this line, be will most likely light up the number 1 (since only 2 segments are lit) (refer to mspaint diagram), while edb will light up the number 7 (since only 3 segments are lit)

for part 1, you are required to find what digits are lit up in your final output, but since digits 1,4,7,8 has an unique number of segments lit up, they can be easily derived

[winged trellis]

oh right.. thanks that makes sense to me

[pearl needle]

you're gonna love part 2

[peak dock]

there are seven segments {a, b, c, d, e, f, g}
if the segments {a, b, c, e, f} are on it diplays 0, if its {c, f} its 1, etc
there are also seven signals {a, b, c, d, e, f}, but they aren't connected to the segment with the same label, its shuffled randomly

the first part of each line (before the |) has 10 sets of signals, and each set of signals will map to a set of segments, and that set of segments maps to a digit between 0-9
the second part of each line (after the |) has 4 sets of signals, which follow the same mappings as the first part, and thus represent 4 digits. this is called the "output value"

the first part of the question asks how many times the digits 1, 4, 7 or 8 appear in the output value

[proud cosmos]

Pretty sure they(recreation) just explained part 2 (at the end anyway)

[winged trellis]

thanks its clear to me 😄

[final eagle]

i mean the logic is the same haha

i just visualized it

[proud cosmos]

When I first saw the problem I was like oh god what is part 2

then I noticed part 1 is just counting some random stuff

At least it still took me hours to do part 2 anyway

[final eagle]

i feel like copilot is a OP intellisense

sometimes i just need to repeat parts of my own code and it does that for me

sadly i cant generate perfect answers

[hollow wharf]

hmmmmmm today's is quite difficult

well, to me

I have a guess as to how to proceed

[pearl needle]

yeah part 2 is the hardest problem we've seen so far

[craggy wraith]

i just read the first part of the problem and i have no clue whats going on

[peak dock]

also takes like 15 minutes to read and understand the problem lol

[minor hamlet]

What’s part 2?

Haven’t got to it yet

[blazing kraken]

The day 8 is hard tho

Tbh

[pearl needle]

you'll have to decipher every digit in part 2

[blazing kraken]

Lol

[minor hamlet]

So brute force?

[pearl needle]

maybe, I dunno

[hollow wharf]

I think there's something sort of pretty here, but I'm going to have a damn hard time writing it

[long scarab]

Day 8 Part 2 is murder!

[sleek lark]

@long scarab part 2 is not that bad. You have to reason in terms of segment and what each number can have in common.

[gloomy kernel]

Hello people

Part 2 is 😅

[fringe temple]

I've had my fill of Python's sets 😅

[blazing kraken]

I still dont undestand todays wuestions

Question*

[iron reef]

part 2 is just laborious, solve it on paper first

[weak torrent]

you gotta read it 5-6 times to understand this

only then you would get to know how crazy part 2 is

also why I am behind people who didn't solve day 8 part 2 on leaderboard?

[devout tusk]

cz you perhaps didn't solve day 8 part 2.......? 🤔

[weak torrent]

I did

[devout tusk]

they solved rest of the parts faster than you did

which made their score better than you despite them not solving day 8 part 2

[hazy pendant]

BRUHHHHHH

I DID A MISTAKE BY ||Not Resetting acc2 after being added to acc||

I GOT 2 GOLD STARS

YAAAAAAAAY

[bright spindle]

That means they were very fast to solve earlier puzzles compared to you.

[loud yew]

i just looked at the puzzle for today... im screwed

[bright spindle]

Given n people on the leaderboard, if you are the i:th person to solve a puzzle, you get n - (i - 1) points. It's entirely possible to score so many points on earlier days that some people can't catch up to you on later days even if they solve all puzzles.

[sonic silo]

that i never get cause like

theres this private leaderboard i am competing with a friend with and like

yesterday he suddenly got 8 more points over me, even though i was just second and he was first

for that specific puzzle

we were at the same amount of points before that

i shouldve just had a 2-point difference, not 8

[pearl needle]

i mean, you can make your own private leaderboard for just you and your friend

[bright spindle]

Let's say there are 100 people on a leaderboard. I solve one puzzle first on day 1, so I get 100 points. You solve part 1 and part 2 for both day 1..8 last, so you get 1 point per puzzle. You now have 16 points. I'm still way ahead of you.

[pearl needle]

you can be a part of multiple leaderboards

[sonic silo]

oh well

[bright spindle]

Are you two alone on that leaderboard?

[sonic silo]

no

[bright spindle]

Then how many points you get depend on when other people on the board solve puzzles as well.

[sonic silo]

hmmmm

[bright spindle]

If you are first, you get N points. If you are last, you get 1 point.

[hazy pendant]

[bright spindle]

What probably happened is, he solved the puzzles yesterday, then some other people solved the puzzles for yesterday, then you did, so you dropped behind depending on the number of people solving puzzles inbetween you.

[sonic silo]

oh well

[hazy pendant]

btw, can people farm points by joining almost every leaderboard ever?

[bright spindle]

No, each score is specific to that leaderboard.

[hazy pendant]

oh wait, there's no global scores

[bright spindle]

They aren't summed across leaderboards.

[hazy pendant]

👍

btw i got the 2 stars

pog

[void ocean]

can we all collectively thank AoC for buffing up our GitHub activity

[hazy pendant]

lmao

i store my solutions the propreitary way

[loud yew]

i finished part 1, and now i am realizing just how screwed i am

[bright spindle]

Yeah, part 1 is pretty easy compared to part 2 today.

[hazy pendant]

part1 is nothing compared to part2