The Nineteenth Byte

New Posts

00:12

0

Q: AoCG2021 Day 18: Stripping Strips

Part of Advent of Code Golf 2021 event. See the linked meta post for details. The story continues from AoC2018 Day 3. _But you're not Bubbler, you're Lyxal! yeah, I know. After a long period of chaos, the Elves have finally agreed on how to cut the fabric. Unfortunately, the next day they have c...

lyxal

shh I totally didn't forget to post it for a bit because I was busy with PR reviewing lol

pxeger

00:28

ever have that moment where you see a person you recognise from one online context in a completely different one?

lyxal

that's basically whenever I use discord but yes

pxeger

I just found niedzejkob (code golfer) on tokio.rs (rust async library)'s blog

and apparently they're also a member of a CTF team: p4.team

Fmbalbuena

00:45

someone can sub my youtube channel?

OldSandboxPosts

01:00

Sandbox posts last active a week ago: Nth FizzBuzz Number

grandBagel

@OldSandboxPosts ...but I already posted it.

caird coinheringaahing

If you don't edit the post down to a stub, OSP doesn't know it's been posted

grandBagel

oh

i forgot to

caird coinheringaahing

No worries, I just did it :)

Fmbalbuena

@cairdcoinheringaahing remove the message

grace period has been passed.

caird coinheringaahing

01:03

OSP's message? Nah, moving it takes the same amount of space as leaving it

grandBagel

@cairdcoinheringaahing Thanks

caird coinheringaahing

→ 1 message moved to Trash

Why?

Fmbalbuena

just for fun.

grandBagel

Woah can you do that in one click? (right click + move to trash)

caird coinheringaahing

No, it takes a bit of effort

Room -> move messages -> Type "Trash" -> Relocate

lyxal

01:06

do y'all ever just wonder why changes you're making to your code aren't working only to realise you're trying to test on production instead of localhost?

Riker

yes. and then I feel like an idiot every time

lyxal

okay good I'm not the only one ;p

Riker

normally i'ts a sign of 'maybe i'ts a bit late to be coding something that matters' :P

hyper-neutrino

01:23

my least favorite thing about the move messages feature is that it is right below the delete room button

and deleting a room only brings up a js confirm prompt and nothing else

it doesn't like ask you to type the room name or type your name to confirm you want to do it or something and sure, rooms can be undeleted just as easily, but it kicks out everyone and is still feels like it'd be a pain to deal with

pxeger

@hyper-neutrino TIL that only mods can delete rooms - not even ROs

hyper-neutrino

yeah the three mod controls in the room dropdown are freeze, delete, and move/delete messages

and i think normal ROs should see five options in the RO controls but mods don't see move messages because that'd be redundant so we just have the other four

Riker

@hyper-neutrino hot take: maybe people should send less messages that need to be moved then :P

hyper-neutrino

lol

like granted the solution is just "git gud lol" especially since "move/delete messages" is longer than "delete room" and so it sticks out to the right more and you can click that but it's still not great that i can delete this room in three clicks

lyxal

@hyper-neutrino what do you expect? SE-chat to actually be quality?

caird coinheringaahing

01:35

@hyper-neutrino I get "schedule events", "manage feeds", "control access", "timeout" and "move messages"

tjjfvi

Wat, you don't need to be an RO of the target room when moving messages?

in Fun misinterpretations, 59 secs ago, by tjjfvi

→ 1 message moved to Trash

hyper-neutrino

nope, you only need to be able to send messages there

@cairdcoinheringaahing is it in that order?

caird coinheringaahing

Yes

pxeger

@tjjfvi moving messages is pretty buggy in many ways tbh

you can move pinned messages, and they stay pinned, for instance

caird coinheringaahing

@tjjfvi No, but it's probably the easiest way to get kicked from a room and have your moved messages trashed

e.g. if someone moved messages into here without asking beforehand, at minimum, we'd tell them to not do it again, and at max, kick-mute them and trash the messages

tjjfvi

01:42

Makes sense

Hence why I moved to trash and not to here :P

caird coinheringaahing

Even more interesting, is that I don't think you need access to a room to move messages there

At least, with gallery rooms. I don't know about private rooms

tjjfvi

...science?

caird coinheringaahing

Feel free to try to move something into The Nineteenth Bakery

lyxal

can't

name doesn't come up

pxeger

oh, because it's gallery?

caird coinheringaahing

01:46

I'm guessing its the same with private rooms too

lyxal

nope

you can move to private

caird coinheringaahing

I'm guessing you're trying to move it to a private room you have access to?

lyxal

yeah

caird coinheringaahing

Then yeah, that should work :P

I don't think there's even a way to move messages to private rooms you don't have access to, as you can't search for them

tjjfvi

@lyxal Doesn't work with editing the request either

Redwolf Programs

01:54

SE usually just pretends private rooms/messages within them don't exist, and 404s

tjjfvi

Yeah that's what it did

caird coinheringaahing

Yeah, given that they're supposed to be private as possible, it makes sense that there aren't any edge cases :P

pxeger

although you always know a room exists because the numeric IDs are consecutive

and the same with messages

although I suppose the room could have been deleted, and there'd be no way to tell what happened

caird coinheringaahing

10k+ users can see deleted rooms

tjjfvi

10k+ on at least one site, or 10k+ total, or what?

caird coinheringaahing

01:58

10k+ total network rep, only counting sites where you have 200+ rep

Redwolf Programs

Wish there was a way to search for questions where all answers were below a certain score

Don't wanna have to try using SEDE on SO

I'm slightly confused by my YT ads recently...baby diapers, women's vitamins, and retirement planning. I'm a 16yo male.

lyxal

retirement planning?

does that mean there'll be a RO position available soon? ;p

also, what's their name (your advertised child that is)

caird coinheringaahing

Do diaper adverts typically name the babies shown?

lyxal

no, but Redwolf being advertised baby diapers implies that there's a child somewhere

hyper-neutrino

02:14

you really just need RO at the source and write perms at the destination

→ 1 message moved to hyper-neutrino's domain

so yeah, you can move into deleted rooms too

Redwolf Programs

02:28

That's just a mod thing tho, right?

Or is it so cursed an ordinary user can just make a room and move stuff from it into a deleted one

New Posts

0

Q: Square root in assembly with least instructions

Write a program that finds the integer square root of a number, the number can be a constant and the square root can be outputed in any way such that another program can get it (like stdout or the exit code), also the program must work on either x64 or x86 assembly (#include and %include are not ...

math assembly

tjjfvi

@RedwolfPrograms Have you double-checked the cat image?

hyper-neutrino

@RedwolfPrograms well all you need is write perms, and only mods can send messages to deleted rooms, so yes it's mod only

not explicitly mod only but since non-mods can't talk in deleted rooms therefore it's by extension mod only

Redwolf Programs

03:12

@tjjfvi Which one? The one in my cop?

If so, yes, I've verified it contains the correct hidden message

tjjfvi

Cool, thanks

You say only one channel matters; I assume it is always the same channel?

Redwolf Programs

Yep

tjjfvi

I'm having trouble identifying which blocks are garbage

This is the best I have so far

But I don't think it's right

Redwolf Programs

There is a way to do it automatically and without too much difficulty, hint 2 is relevant

tjjfvi

So this is what I'm starting with

It looks like there's data in both "black regions" and "white regions"

And it seems that the first pixel of each block is usually the inverse of the background

Inverting the blocks based on the first pixel yields

user

03:21

What are you doing to that poor llama?

tjjfvi

Interrogating it

Redwolf Programs

@tjjfvi Quick warning, that looks like some of the pixels have been incorrectly changed

tjjfvi

That isn't flipped at all

That's just %2 of the red channel

Redwolf Programs

Wrong word sorry

Meant flipped as in the bit flipped

tjjfvi

By "some", do you imply "not all"?

I'm not flipping anything there

@tjjfvi This image is just %2 of red

@tjjfvi This is that with some flipping

Redwolf Programs

03:24

Wait, no, I'm just getting thrown off by the darkness being inverted from what I'm used to

Ignore me

It looked like there were some artifacts from something or other

tjjfvi

Ah ok

@tjjfvi So, back to this

It seems like all the "data-looking" blocks have a white row at the top

Redwolf Programs

That's mostly coincidence

tjjfvi

@tjjfvi Filtering the blocks for that yields this

But that still seems to have garbage...

This image was generated from the diff:

(I know the diff isn't needed, but)

Redwolf Programs

This part seems to have been difficult for either of y'all to figure out, and I guess it is a bit non-obvious, so here's a bit of a big hint: the top left pixel is a parity bit

tjjfvi

That's what I thought

Maybe I misinterpreted that, though

@tjjfvi Is this not the right interpretation of "parity bit"?

I took it as "to flip or not to flip"

Redwolf Programs

03:29

Parity bit as in it's toggled to ensure the total number of zero bits is always even (or odd, depending on the scheme)

tjjfvi

Oh...

That looks better (I think?)

Redwolf Programs

Yep! That looks a lot more promising

tjjfvi

Now I need to figure out what to do with these blocks

(and if any are still garbage...)

Redwolf Programs

I think you and GingerIndustries are about tied now

tjjfvi

My best (untested) guess atm is that characters are encoded in columns and the top row has special handling

That would leave only 7 rows, but that's fine bc ascii is 7-bit

Redwolf Programs

03:38

After lots of looking I don't see any blocks there that look like garbage blocks, so I think you're doing that right

tjjfvi

Awesome thanks

My guesses for the top row are:
- ignored (seems unlikely)
- flips all lower bits
- marks a column as invalid

But these all feel like shots in the dark

Redwolf Programs

I'd recommend picking a random one of those blocks, probably one in the sky, and looking at any patterns it has in detail

I tried my best to add some hints at the structure, and a bit of redundancy against possible mistakes or amiguities

tjjfvi

Ah

Now I see how your third hint starts to come in

Wait, not everything is symmetric

nvm

I'm blind as usual

Thanks for the fun challenge btw

Redwolf Programs

I'm considering a second cop, I guess I should go get more pictures of my cats

tjjfvi

lol

^ this chunk really captures how I feel trying to crack this

Redwolf Programs

03:56

lol

I have a cool idea for a cop, but it's going to be tough to actually do

AviFS

04:20

Hi everyone!!

Also, @RedwolfPrograms, there may or may not be something for you to check on Discord.

tjjfvi

04:34

Hmm, I have 1 block per character, but there aren't any duplicate blocks in the cat afaict

I guess there must be some data redundancy

Unrelated String

06:30

@GingerIndustries it was pretty straightforward to decode by hijacking the flow of what i used to encode it in the first place

PyGamer0

how to win at videogames:
- get good at math
- get good at physics
- figure out how game physics work
- exploit them or use that knowledge to your advantage
- Profit!

lyxal

alternatively, use linux and just TAS it

New Posts

09:10

0

Q: The Most Wanted Prime Numbers

Output a sequence of all the primes that are of the following form: 123...91011...(n-1)n(n-1)..11109...321. That is, ascending decimal numbers up to some n, followed by a descending tail, all concatenated. Background Recently, Numberphile posted a video about primes that follow this pattern. Outp...

code-golf sequence primes

Neil

10:28

Top 15 languages used to answer AoCG questions so far, with counts of questions answered in that language:
18 Charcoal
18 Pari/GP
18 Python
18 TypeScript Types
17 Rust
16 Ruby
15 Mathematica
14 05AB1E
14 JavaScript
11 R
7 BQN
6 Java
5 J
5 Jelly
4 Retina

New Posts

11:37

0

Q: Should we let Vyxal Bot into TNB when Vyxal is the LYAL

Context: Given that Vyxal is roughly under a month away from being selected for LYAL (at the time of posting, my calculations place it as being 1-2 LYALs away), I figured I'd write this so it can garner feedback and hopefully approval in time. Over in the Vyxal chat room, we have a neat little bo...

discussion chat chat-events

lyxal

Asking now for planning purposes

because it might even end up being longer than a month away if people vote enough for other languages

lyxal

12:01

speaking of LYAL planning,

CMQ: What have you enjoyed/disliked about previous LYALs?

and what would be the one thing you would recommend/change to make a LYAL better?

New Posts

0

Q: Binary with 0's only

The input message consists of ASCII characters The encoded output message consists of blocks of 0 A block is separated from another block by a space Two consecutive blocks are used to produce a series of same value bits (only 1s or 0s): After the ACSII character(s) have been converted to binary, ...

code-golf code-challenge

Unrelated String

what's the line about permission to use challenges/other content again
because this is transparently from some other site and the spec linked is some third person's solution to the other site's problem

of course it also needs to be pointed out that a word salad and then a link to an external spec is the opposite of self-contained, the output format might be too restrictive, please use the sandbox next time, etc.

lyxal

do you think it's a good idea to answer it?

because I have a 17 byte fgitw ready

Unrelated String

probably not? i forget what the whole deal is though

~~just post a hash of it here in case~~

nrgmsbki4spot1

I would like to leave the internet for at least a year because I have seen some nasty things on other communities whom I have never done something with and I have been producing nasty news recently.

Bubbler

12:27

> ACSII

lyxal

American Candard Stode for Information Interchange

5

caird coinheringaahing

13:22

@UnrelatedString They need permission from the original author, and they need to credit that author

Ginger Industries

14:16

mornin

Fmbalbuena

15:05

CMC: how to return 1234...n(n+1)n...4321 in Python 3?

user

15:44

How does that range even work?

Fmbalbuena

example n = 10: 12345678910987654321

hyper-neutrino

15:59

first of all that didn't go up to n+1

and do you want a list? a string? a single large number?

Fmbalbuena

integer

tjjfvi

@RedwolfPrograms Is the placement of the chunks relevant?

Fmbalbuena

Any feedback?

tjjfvi

16:15

"Check if a string X is such that: there exists a strict prefix Y of X such that X is a prefix of Y + Y"

is ^ a correct interpretation?

Fmbalbuena

i don't understand

tjjfvi

(where the strict prefixes of "abcd" are "", "a", "ab", and "abc")

Wezl - a cautionary tale

I'll probably be here more often now because my school district just switched back to "distance learning"

tjjfvi

So `"abcd"` is not a "reshaped" string, because:
- `"abcd"` is not a prefix of `""`
- `"abcd"` is not a prefix of `"aa"`
- `"abcd"` is not a prefix of `"abab"`
- `"abcd"` is not a prefix of `"abcabc"`

hyper-neutrino

@tjjfvi no, because Y could be repeated more than twice

tjjfvi

16:18

That's still valid though

hyper-neutrino

frick

yeah lol

tjjfvi

abcabca is a prefix of abcabcabcabc

Fmbalbuena

@tjjfvi no

tjjfvi

@tjjfvi But abca is, because abca is a prefix of abcabc

Fmbalbuena

So `"abcd"` is not a "reshaped" string, because:
- `"abcd"` is not a prefix of `null*4`
- `"abcd"` is not a prefix of `"aaaa"`
- `"abcd"` is not a prefix of `"abab"`
- `"abcd"` is not a prefix of `"abca"`

hyper-neutrino

16:18

rather I should say your interpretation is not word-for-word correct to the intent of the spec but is an equivalent problem

tjjfvi

Equivalent, but possibly more intent-preserving: "Check if a string X is such that: there exists a strict prefix Y of X such that X is a prefix of Y repeated N times, for some N"

Fmbalbuena

@tjjfvi should i put to title?

tjjfvi

I think using reshaped in the title is fine/good

hyper-neutrino

"check if a string X has a strict prefix Y such that Y can be reshaped to X" and then just define reshaping properly

Fmbalbuena

@hyper-neutrino then i can put to the title?

hyper-neutrino

16:22

no your title should not attempt to contain the challenge

tjjfvi

"for all X, N, all prefixes of (X * N) are reshapings of X"

hyper-neutrino

"Check if the string is reshaped" is fine because challenge titles don't need to really contain much information (what does "Dennis Number" even mean? the title doesn't mean anything until you read the problem), but the challenge body needs to be clear

Fmbalbuena

ok

then how to make the challenge body clear?

hyper-neutrino

do you mind if I attempt to rewrite most/all of your current spec?

Fmbalbuena

No

caird coinheringaahing

16:28

Damn, I've done 4 FA and 4 LA reviews today, that might be the most I've ever done in a single day O.o

hyper-neutrino

@Fmbalbuena done

Fmbalbuena

Why chat.stackexchange.com/transcript/message/59919899#59919899 instead of chat.stackexchange.com/transcript/message/59919899?

hyper-neutrino

because that way your browser will automatically scroll down to the message

tjjfvi

reshaped to the size of 4 to obtain "abba"

Fmbalbuena

@tjjfvi ?

tjjfvi

16:33

(a suggested edit)

Wezl - a cautionary tale

talking about challenge clarity, I have an idea for a challenge that I'm not up to writing out clearly. Someone else can take the work and the rep. Basically, taking a list of 2+ control points (points are lists of numbers of any length but the length of all points is guaranteed to be the same) and a number of subdivisions, output the points of the bezier curve with the inputted control points subdivided that many times. (I can write some test cases and an example program too).

(it does not include drawing)

Fmbalbuena

APL implementation: {(⊂⍵)∊(≢⍵)⍴¨¯1↓,\⍵}

hyper-neutrino

do you mean subdivided evenly by arclength or some other division?

Fmbalbuena

Taked from this.

Wezl - a cautionary tale

@hyper-neutrino ... the subdivisions kind of depend on a specific algorithm that I don't exactly know how to explain

hyper-neutrino

16:38

hmm.

Wezl - a cautionary tale

oh wait I phrased the original message wrong because I misremembered

Fmbalbuena

how to get the prefixes of the string in Python 3?

hyper-neutrino

you should post the challenge before coming up with more solutions for it and you also probably shouldn't post solutions and let other people solve it first

Fmbalbuena

ok

delete the message?

Wezl - a cautionary tale

@Wezl-acautionarytale the algorithm is to (for example) if the subdivision number is 3, for each fraction 0/3, 1/3 ... 3/3 f, take the points f of the way from each control point (but the last) to the next control point, then repeat that process on each of those points until it reduces to a single point. Then you have a point corresponding to each value of f. Return these points

hyper-neutrino

16:43

oh, so just subdivide based on the parameter

i was gonna say subdividing a bezier curve by arclength is impossible to get precise and you have to just approximate lol

yeah, I think that'd be a decent challenge. do you want to write it up now that you have a better description of the algo or do you still just want someone else to take it?

Wezl - a cautionary tale

if I have any volunteers, they can go for it

hyper-neutrino

alright, sure I'll sandbox it then

Wezl - a cautionary tale

tysm

Bézier curve

A Bézier curve ( BEH-zee-ay) is a parametric curve used in computer graphics and related fields. The curves, which are related to Bernstein polynomials, are named after French engineer Pierre Bézier, who used it in the 1960s for designing curves for the bodywork of Renault cars. Other uses include the design of computer fonts and animation. Bézier curves can be combined to form a Bézier spline, or generalized to higher dimensions to form Bézier surfaces. The Bézier triangle is a special case of the latter. In vector graphics, Bézier curves are used to model smooth curves that can be scaled ...

New Posts

0

Q: Kolmogorov-simple numbers

If you visit Code Golf often, you may have heard of Kolmogorov complexity. It's usually defined as the amount of bytes required to express some string in a programming language. Here the Kolmogorov-complexity of a natural number is defined similarly: the number of bytes required to represent it i...

code-golf kolmogorov-complexity open-ended-function

Sandbox Posts

17:20

0

A: Sandbox for Proposed Challenges

Subdivide the Bezier Curve Background A Bezier curve is a type of curve that has a lot of applications in all sorts of places, but most commonly, in computer graphics. It has a very simple algorithm and yet can represent a wide variety of shapes with just one common formula. If you've ever used p...

Fmbalbuena

17:50

Crogramming Guzzles & Code Colf

Redwolf Programs

18:15

It's expected to be 80°F this christmas :(

Unrelated String

yikes

Redwolf Programs

Like I mean I might as well be doing SE Summer Bash, I don't live in the southern hemisphere but it hasn't dropped below like room temperature outside in a month

@nrgmsbki4spot1 Do you mean other SE communities, or other internet ones?

@tjjfvi Well, in a way. It's hard to say without revealing more than I should.

But the encoding of the character values themselves are not dependent on their locations

New Posts

0

Q: Multiplicity of Shared Totients

Euler's totient function, \$\varphi(n)\$, counts the number of integers \$1 \le k \le n\$ such that \$\gcd(k, n) = 1\$. For example, \$\varphi(9) = 6\$ as \$1,2,4,5,7,8\$ are all coprime to \$9\$. However, \$\varphi(n)\$ is not injective, meaning that there are distinct integers \$m, n\$ such tha...

code-golf sequence number-theory

Sandbox Posts

18:36

0

A: Sandbox for Proposed Challenges

Find duplicates, quickly In this challenge, you'll be given a list of positive integers or non-empty alphabetical strings (your choice), and must return a list containing all duplicates. You must do this with the minimum time complexity you can, and as few bytes as possible. Task: Given a list of...

Redwolf Programs

So uh...I got captcha'd on that for some reason, but the captcha solved itself

@SandboxPosts Before anyone comments that there's some trivial way of getting a low time complexity on this, that's sort of the point. I like the idea of using this combination of fastest-algorithm and code-golf, since it'll make it primarily a code golf competition once somebody figures out a good algorithm, but it more organically prevents boring brute forces

hyper-neutrino

@NewPosts the hard part of this challenge (IMO) is figuring out the upper bound

Redwolf Programs

^

hyper-neutrino

at least to me, it's not immediately obvious what the max possible value with totient k is otherwise it'd be a trivial range-filter-count

caird coinheringaahing

It feels like n^2 should work for n > 2, but I don't know about it

hyper-neutrino

18:42

according to math.stackexchange.com/a/23977/457091, $\sqrt{n} \leq \Phi(n) \leq n - 1$

so yes you are correct caird :p

caird coinheringaahing

(n+1)^2 will work for all n then

hyper-neutrino

wait, i'm dumb. filter equals → length is literally just count kekw

caird coinheringaahing

You can remove the R as well :P

hyper-neutrino

i can?

caird coinheringaahing

On your filter one, not the count one

hyper-neutrino

18:46

not after i removed the filter

right

Adám

caird coinheringaahing

Jelly needs an atom that does something like "generate a range that gives you plenty of extra numbers beyond a bound" :P

Adám

W⍺ randomly does or doesn't understand 8^2000000000

Redwolf Programs

19:04

Posted a second cop:

0

A: Hide a message in an image - Cops

The sort you'd expect Image 1: These are colorful for a reason! Image 2: Stock photos FTW Image 3: Crack this one!

This one should be a little more fun, but also a bit tougher

Redwolf Programs

19:24

Ignoring all the PIL/canvas interaction stuff, it only has like two lines of actual logic, so it doesn't have nearly as many steps you need to reverse engineer

Ginger Industries

'sup

Redwolf Programs

Hi!

Ginger Industries

did you know that compiling cmake 3.22.1 on a raspberry pi is very time-consuming

@RedwolfPrograms workin on your stego

Redwolf Programs

Which one?

Ginger Industries

latest

Ginger Industries

19:46

@RedwolfPrograms after conducting an alpha scan:

Redwolf Programs

:)

Ginger Industries

✨it's garbage✨

there is far too much data in here for a few words of text

@RedwolfPrograms i take this to mean i'm on the right track

Redwolf Programs

You are

Ginger Industries

oh baby

more encoding system gibberish

i'm so very happy

Redwolf Programs

This one's not as complex of an encoding system

Ginger Industries

19:50

k

there's a lotta data

i'm guessing that the position of the pixels matters

it's 470x200, which gives us 40 bytes vertically and 58.75 horizontally

hmm

actually

that's 11750 bytes total

@RedwolfPrograms output using the good ol' "assume each byte is a codepoint" system:

  0@|@N	 		}/@@0``"7X ~XD
                                      p`H@
                                          @"p@@epc  @W
D i`
    h *P@@]`Fx@8@@3p%X
                      	 `p
                           n

 @ `o@`|4PgP0(6(}n
                  $
                    @`
xB@^Hp@ @9     O|, X@@@@NH `@`  D@
'pB0
    Cp $a~@
           	qP`@(~@@8? C@ L
_pH @?0Bow|A8  @_{~@~(@#?~!x0@`,_@
                                  a;C  @b@?~
                                            p5PPw_~@5 _ax@4
                                                           @gppx

more ✨garbage✨

Redwolf Programs

Two very big hints added

Ginger Industries

oh boy

I think i oughta take another look at that alpha image

if each letter thing is 8*8

hm

sussy

Redwolf Programs

20:10

Please don't split it into 8x8 blocks, I wouldn't use that twice and you'll waste a long time doing it

Ginger Industries

okay nvm

¯\_(ಠ_ಠ)_/¯

@RedwolfPrograms how about 32x32 blocks

mind blown

Redwolf Programs

nooooo

Ginger Industries

how about 128x128 blocks

Redwolf Programs

> Ignoring all the PIL/canvas interaction stuff, it only has like two lines of actual logic, so it doesn't have nearly as many steps you need to reverse engineer

Ginger Industries

how about 65536x65536 blocks

well, the 10th byte in the alpha turned into bytes is 0010010

that's not very helpful

in integer that's 18

which is the letter s in the alphabet

lemme do that to evry byte

WAIT I JUST HAD AN IDEA

what if each byte is actually part of a smaller image IN THE OTHER IMAGE

@RedwolfPrograms ^

first 16 bytes of the alpha: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 18, 32, 0, 0, 22, 27]

Ginger Industries

20:40

I return

Sandbox Posts

20:59

0

A: Sandbox for Proposed Challenges

Can we patch the corona certificate validation code (part 1/3)? The new chancellor of Germany, Mr. Olf Scholz, is in deep trouble: the Covid app does not show the vaccination status correctly beginning with booster vaccinations. He was not involved in the development of the app, since that was un...

Thomas Weller

Hey guys, you're so awesome. You have automatic notifications about sandbox posts. Cool! I was inactive here for a long time and have not followed the new meta rules, so I think I need some feedback on my challenge. Thank you!

Ginger Industries

@ThomasWeller we'll look into it

Ginger Industries

21:16

@RedwolfPrograms is the data for this encoding just in the alpha, or is it also in the color channels?

Riker

@ThomasWeller interesting question, looks fun. i like it

Ginger Industries

@ThomasWeller seems good to me

@Riker you know, these could be good for AoCG

Riker

@GingerIndustries that problem? too simple for an advent problem imo

hm, no actually

for AoC yea but for AoCG nah

Ginger Industries

yes, we do have lower standards here at Pode Polf Cack Gxchange

Riker

definitely a fun little series of 3 challenges though, i'm interested to see what hte other two end up as

Redwolf Programs

21:30

@GingerIndustries I can't tell exactly what you're saying, but I think you're sort of on the right track

Did you read the two hints?

Ginger Industries

yes

@RedwolfPrograms now i'm trying to do an emanresu A with each row

Redwolf Programs

Okay it sounds like I should probably give another hint then

Ginger Industries

¯\_(ಠ_ಠ)_/¯

Redwolf Programs

What you're looking for is a black and white image the same size as the original image

Ginger Industries

i SEE

alrighty then

maybe if I keep each pixel with a changed alpha

Redwolf Programs

21:33

I'm not going to give any more hints for a while, but you should definitely look at hint 1

Ginger Industries

okay, got it

:)

Redwolf Programs

CMQ: If you could star your own (already starred) messages, roughly what percentage of them would be yellow?

Ginger Industries

@RedwolfPrograms probably 30-40%

i find myself very amusing

@RedwolfPrograms Okay, my new algorithm is grinding away

it'll take about 2 minutes to finish

about 1/6 done

Redwolf Programs

Ooh, what is it?

Ginger Industries

@RedwolfPrograms it just filters out pixels in the image that have an alpha of 255

but it's very inefficient

so

halfway there

only 90 rows left

50 rows

aaaand

it crashed

:/

wait is hint 1 a goddamn pun

the sort you'd expect

@RedwolfPrograms ^

as in sorting items

Redwolf Programs

21:51

:)

Ginger Industries

really

@RedwolfPrograms ಠ_ಠ

@RedwolfPrograms Well, I've sorted the 8-byte group things, converted them to ints and counted them

i am getting no wisdom

Redwolf Programs

You're still not quite on the right track

Ginger Industries

sort by color?

@RedwolfPrograms ^

imma do that

well, i'm going to assume that the alphafied pixels are important

maybe if i sort the others by color

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