The Nineteenth Byte

Anonymous

00:01

@feersum If new == old, then the value is 0. But, there are an infinite number of alternative possibilities, so new == old has probability 0.

feersum

The number of possibilities seems finite to me. You can only store so much code in the observable universe.

noɥʇʎPʎzɐɹC

Tip: add . to $PATH

Dmitry Kudriavtsev

No. Don

t.

Anonymous

@feersum If a number can't fit on a chalkboard, it's essentially infinite.

noɥʇʎPʎzɐɹC

?

then you can execute scripts in the current working dir

Dmitry Kudriavtsev

00:05

Someone made a thing where they put an executable file named ls in a directory.

feersum

That makes no difference since you can have a universe-sized chalkboard.

Dmitry Kudriavtsev

It wipes the home directory.

noɥʇʎPʎzɐɹC

@DmitryKudriavtsev that dude shouldn't have access to your home directory...

they could've wiped it directly

Dmitry Kudriavtsev

no, it was like a flashdrive or something

noɥʇʎPʎzɐɹC

and it should require sudo

Dmitry Kudriavtsev

00:06

open it, run ls, and bam

ASCII-only

@noɥʇʎPʎzɐɹC Seriously, don't, just ./script is fine

Dmitry Kudriavtsev

actually, you own your home directory, so it does not require sudo

have fun losing all your files

feersum

If the attacker can insert foreign objects into your machine, you have probably already lost.

Dmitry Kudriavtsev

It's not the attacket.

For example, you pick up a flash drive.

Insert it (terrible idea)

feersum

If you're the attacker -- even worse!

Dmitry Kudriavtsev

00:10

I only insert random flash drives on a separate testing machine, and only after taking a btrfs snapshot

quartata

@feersum If so then gdb is lying to me

@Mego One second let me clean it up

feersum

There's no way to identify stack corruption in general.

Remember, the stack includes local variables, not only return addresses.

quartata

I can access all of the other members of the class though

Dmitry Kudriavtsev

wikiwand.com/en/Place_names_considered_unusual

ASCII-only

@Everyone help, what order should uppercase/lowercase/numeric/whitespace/symbol be in for maximum compression for ASCII-art challenges?

Anonymous

00:13

@feersum Alright, fine. Since you want to make this more difficult than it needs to be, let's do the math. The universe can contain a maximum of about 10**123 bits (computing the Bekenstein bound of the observable universe). Therefore, the probability of two programs containing exactly the same number of bytes is 10**(-123). That's essentially 0.

quartata

#include <cstdio>
#include <vector>
#include <ucontext.h>

#define IDLE 0
#define RUNNING 1
#define DONE 2

class PytekGenerator {
public:
  std::vector<int> results;
  ucontext_t generator;
  ucontext_t me;
  int state:2;

  int operator[](int index) {
    state = RUNNING;

    while (results.size() <= index && state != DONE) {
      swapcontext(&me, &generator);
    }

    return results.at(index);
  }

  PytekGenerator() {
    state = IDLE;
    results = std::vector<int>();
  }
};

PytekGenerator* result() {

Sorry for the horrid C++

It's probably a ucontext thing. I'm going to try pthreads instead

Geobits

It should be 1) symbol 2) kanji 3) hangul 4) lower 5) numeric 6) whitespace 7) upper

Dmitry Kudriavtsev

it's called cout

feersum

Hangul is really good if you need to draw space invaders.

ASCII-only

But how would I compress Kanji/Hangul

Geobits

00:14

The same way you compress other characters?

ASCII-only

But I compress using base conversion

Anonymous

@quartata The issue might be due to the fact that your vector isn't marked as volatile

Anonymous

~~Also you never seem to initialize the me context~~ oh wait swapcontext

Dmitry Kudriavtsev

this article is very funny:

wikiwand.com/en/Fucking,_Austria

quartata

I'll try marking it as volatile. It's worth noting that if you comment out the push it segfaults at the generator swapcontext so

->state is fine though

Anonymous

00:21

You might want to mark state as volatile also

Anonymous

Anything that can be changed by multiple threads should be volatile

Anonymous

That will keep the compiler from trying to be smart and "optimize" things (which actually breaks everything in multithreaded programs)

feersum

Weeell you should really never use volatile for multithreading...

Anonymous

@feersum Yeah, locks/mutexes are much better. But, volatile makes more sense in this case.

DJMcMayhem

Yeah you should

feersum

00:27

As this case isn't multithreading at all.

Anonymous

Since contexts aren't quite multithreading - only one thread is running at a time, but you swap between them

feersum

I guess you can try throwing random voodoo at it such as volatile.

Anonymous

volatile isn't random voodoo

feersum

There's no clear reason why it should help.

DJMcMayhem

Oh, are you working with interrupts?

quartata

00:29

No with something far worse

Anonymous

@feersum Sure there is - the problem could very well be due to hyperaggressive optimization by the compiler, which volatile helps solve.

quartata

ucontext

Conor O'Brien

I need to read an image into an rgb array. which language should I use if python hates me?

feersum

@Mego Can you give an example of an optimization that could be problematic in this scenario?

ASCII-only

@ConorO'Brien JS if it's PNG, JS if it's PNG/JPG/GIF

Conor O'Brien

00:31

@ASCII-only command line.

quartata

Java's ImageIO is great

Downgoat

@ConorO'Brien brb adding image IO to cheddar and then responding here saying cheddar

Conor O'Brien

@Downgoat :D please do

Downgoat

powerful, but easy image IO was one of first reason i made cheddar

quartata

one call and you have a bufferedimage that you can getRGB to your heart's content

Conor O'Brien

00:33

I'm not making a java project to do a simple scripting task

quartata

groovy then

feersum

Then make 1 file in a text editor?

quartata

@ConorO'Brien I know Java gets a bad rep in general for verbosity but this is actually something it's good at and it's super short

Sample:

Downgoat

@ConorO'Brien ;_; y u not use node + npm module

Conor O'Brien

@Downgoat because png-js will be the third module tried.

Downgoat

00:38

try dis?

ASCII-only

@ConorO'Brien They don't work?

Conor O'Brien

@ASCII-only if they did I wouldn't be trying more now would I :P

ASCII-only

@Downgoat ninja'd

@ConorO'Brien Why would they not work

Anonymous

@ConorO'Brien Python doesn't hate you.

pip install pillow && python -c 'from PIL import Image; img = Image.open("whatever.png"); print([[img.getpixel((x,y)) for x in range(img.size()[0]] for y in range(img.size()[1])])

'

quartata

ImageIO.read(file url...).getRGB(x, y)

ez

Conor O'Brien

00:38

sure it does. `'pip' is not recognized as an internal or external command,
operable program or batch file.`

I tried installing pip. it uninstalled itself

quartata

@ConorO'Brien python3 -m pip install pillow

If you really dislike public static void main then just use Groovy

DJMcMayhem

^^

Anonymous

@ConorO'Brien You're using Windows. There's the source of your problems. Make sure your Python bin folder is on your %PATH%

Conor O'Brien

@Mego it is.

Anonymous

Specifically, <python dir>\Scripts

quartata

00:41

import javax.imageio.ImageIO;

def image = ImageIO.read(new URL("file:///home/quartata/test.png"));

print image.getRGB(0, 0);

That sure was a lot of typing

Anonymous

Or just use Cygwin/alwsl and avoid all of those problems

Conor O'Brien

@quartata dude i get it. bc I'm not responding to you doesn't mean I didn't see your messages >_<

DJMcMayhem

Is alwsl finished? I thought he was still working on it

quartata

Just demonstrating. Not all the memes about JVM languages are true

Conor O'Brien

@quartata I honestly like Java.

quartata

00:42

@DJMcMayhem For what I've seen it's usable-ish

Anonymous

@DJMcMayhem It's usable enough to run pip and simple Python scripts, from my understanding

Conor O'Brien

@quartata I think I'll try groovy

ASCII-only

@DJMcMayhem He is, but it's more than usable enough, it can run Firefox pretty well

@quartata But Groovy != Java

The memes about Java are true, but Java isn't the only language on the JVM

quartata

@Mego I tried slathering volatile in it and got a nasty compile-time error since apparently volatile std::vector is a different type

But somewhat amusingly

ASCII-only

Not entirely sure how well Python/Ruby work in the JVM, but they may work as well

quartata

00:45

Putting volatile on state caused it to output garbage instead of segfaulting

Anonymous

@ASCII-only Jython works well, and interfaces nicely with Java

quartata

This happened to me before when state was always equal to idle

Strange things happen when you return five times I suppose

What signal does pause() wake up on again?

Any signal?

Looks like it

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Pieces of sushi Given a number N, print N pieces of sushi in the following way: 1st piece always looks like this ,;'''''''';, |',________,'| | | '.________.' Every next piece gets blocked a little by the piece before it and also gets moved a little up ,;'''''''';, ,;'''...

Conor O'Brien

okay guys. I'm the biggest idiot ever to exist. I switched width and height in my svg so it looked weird all the time

I have a wonderful hack that uses four different language but does what I want

I think I'd cause a heart attack to CR

Conor O'Brien

01:20

If I didn't screw anything up, these are the densest characters in Consolas:

 `.-':_",~^!=;><*\/+c?|rLvzT)s(J7[ti{}nuxlC3fI1oFY]yZ5ewajh2SkPE9Vbp6UdqKGmA4OHXRD8#B0M%N$Wg&Q@

(space at the beginning)

ASCII-only

Help, what would the solution be for this in the ideal ASCII_art golfing language

@ConorO'Brien TIL space is one of the densest

Conor O'Brien

densest at the end >_<

ASCII-only

@ConorO'Brien You mean characters by density?

Conor O'Brien

yes

calculated by summing rgb values :P

ASCII-only

@ConorO'Brien 0/10 you could have just turned off ClearType/set hinting to high or whatever and counted the white pixels

Conor O'Brien

01:24

huhwat

ASCII-only

IDK, just without weird half-on pixels they would all have been either foreground or background color

Downgoat

> Remove as many characters as possible without changing the meaning of the condition

CS HW is PPCG confirmed

Conor O'Brien

whoa

ASCII-only

@Downgoat If you had a full code sample (i.e. with variable declarations) you could make it much ~~shorter~~ more unreadable

Downgoat

my god they are using ifs instead of ternaries why

ASCII-only

01:30

@Downgoat Wait where

Conor O'Brien

"Look teacher! I got it down to 49 bytes!" (rest of class: wait mine was like 232) "It's not a contest downgoat" "Oo, another one off!" "... what's wrong with you"

ASCII-only

> downgoat

Conor O'Brien

yes

ASCII-only

^^^ @Downgoat Oh no it looks like your teacher is onto you

PhiNotPi

I want to know your bytecount when you're done with it.

Conor O'Brien

01:32

what good is that if you don't know what he started with ? :P

ASCII-only

I'd guess ~400, it's Java (I think) after all

Dmitry Kudriavtsev

Hey @ConorO'Brien can you do that with 12 point terminus as well? (16px / 12pt)

Conor O'Brien

@DmitryKudriavtsev terminus? is that a font?

Downgoat

@PhiNotPi 185 -> 41

Dmitry Kudriavtsev

yes. my favorite monospace fonts

ASCII-only

01:35

@Downgoat Wait really? Can you post the initial snippet

Dmitry Kudriavtsev

@ConorO'Brien terminus-font.sourceforge.net

Conor O'Brien

@DmitryKudriavtsev is it a linux font?

Downgoat

boolean no = (ch[0] == 'N' && c[1] == 'O') ||
             (ch[0] == 'n' && c[1] == 'o') ||
             (ch[0] == 'N' && c[1] == 'o') ||
             (ch[0] == 'n' && c[1] == 'O');

Conor O'Brien

oh, cool

Downgoat

clearly the book does not understand how to code

Dmitry Kudriavtsev

01:35

@ConorO'Brien There's a Windows installer

Conor O'Brien

cool, will do!

ASCII-only

@Downgoat Ouch, that's like anti-DRY

@Downgoat ch and c?

Downgoat

and she says a ^ 2 is syntax error even though its valid

(you're supposed to do Math.pow(a,2) but it is not syntax error...)

ASCII-only

@Downgoat IIRC they do, statically typed languages suck

quartata

@Downgoat That's true

ASCII-only

01:37

@Downgoat This is xor not power

Downgoat

@quartata WAT

shit now i look like idiot

;_______; i promise i am smart gaot pls

Conor O'Brien

it's okay. we all are idiots, being programmers, but we're the smartest kind of idiot

PhiNotPi

...just make sure you thoroughly test whatever answer you come up with.

ASCII-only

@Downgoat Why is there both ch and c

quartata

@Downgoat Is no their variable name?

Downgoat

01:39

@ASCII-only typo when copying from book

@quartata yes

ASCII-only

@Downgoat Which one is it

Downgoat

ch

quartata

@Downgoat end my suffering

Downgoat

how

quartata

burn that book for a start

ASCII-only

01:41

Something like boolean no = ch.toLowerCase() == "no"? You might need a ch.substring(0, 2)/ch.slice(0, 2) or the Java equivalent

Conor O'Brien

@quartata challenge: switch your code editor's font to the tf2 build font and try to make something

@DmitryKudriavtsev Here's the density table, least to greatest:

  .`:'-,;/^"~_|!+?i><vr7t(c)=s*j51}l{IJ23yezoa[f4]Lxu#V0Tn96YFqCb8wSd$AUpkghPZ%EGNOX&mRDKBHQWM@

quartata

@ConorO'Brien Which font? Source uses a couple

PhiNotPi

Is ` really more dense than .

quartata

also I use vim

Conor O'Brien

@quartata Terminus

quartata

01:44

ok

Downgoat

:O Coda added powerline fonts

Conor O'Brien

@ConorO'Brien @PhiNotPi the density for consolas is in this reply, it makes a bit more sense

Downgoat

@quartata sorry can't, id have to pay huge fine

PhiNotPi

ok, sorry, didn't see that one

Downgoat

also fireplace is borked atm

ASCII-only

01:46

@Downgoat Oh no you need to push a bugfix for your fireplace ASAP

Dmitry Kudriavtsev

@ConorO'Brien Thanks!!!

Conor O'Brien

my pleasure :)

quartata

Who needs a fireplace? Just soak it in gasoline, put it in a metal bin outside and chuck a match in it

If you're feeling ambitious you could try dynamite instead. Bury it with a few sticks on a long fuse

Dmitry Kudriavtsev

@ConorO'Brien Do you like the font though?

Conor O'Brien

I'd use it, but it doesn't have great unicode support

ASCII-only

01:50

@Downgoat Oh wait a second your fireplace == Cheddar?

Downgoat

CMC: golf a>=90?'A':a>=80?'B':a>=70?'C':a>=60?'D':'F'

@ASCII-only ;_;

btw pls use === so my fireplace does not type cast to cheese

Conor O'Brien

@Downgoat which language?

Downgoat

idk, C/C++/Java

i would use array but afaik int[]{} syntax is too long

ASCII-only

@Downgoat Oh no too late

Dmitry Kudriavtsev

hastebin.com/tumazuvica.txt

ASCII-only

01:55

@Downgoat "FFFFFFDCBA"[a/10]?

Dennis

You need an extra A for 100.

Downgoat

@ASCII-only no werk in java ;_;

Dennis

You said C was fine.

PhiNotPi

what font does hastebin use?

quartata

a>=60?'A'+9-a/10:'F' doesn't work for 100

DJMcMayhem

01:58

When this question's title appeared in my sidebar, at first I thought it was a heavy metal lyric. — Crashworks 4 hours ago

Conor O'Brien

6

@quartata

Dmitry Kudriavtsev

oh god

@PhiNotPi I switched it to terminuson my PC

DJMcMayhem

@ConorO'Brien What is that font called?

quartata

Woops, a>59 saves a byte

DJMcMayhem

(For science, of course)

Conor O'Brien

02:01

@DJMcMayhem TF2 Build I think

ASCII-only

@Downgoat What happens

Conor O'Brien

I got it off the tf2 wiki

Downgoat

@ASCII-only bork

Dennis

@PhiNotPi For what? Code?

Downgoat

@quartata output number no string

ASCII-only

02:01

@Downgoat Bork how

quartata

It's what TF2's default HUD uses for item names

Downgoat

@ASCII-only bork meaning full bork (i.e. syntax bork)

Dmitry Kudriavtsev

this piece looks like c code: vr7t(c)=s*j51}l{IJ23yezoa[f4]Lxu

ASCII-only

@Downgoat Output char not number

quartata

@Downgoat That's what chars are.

Although it shouldn't promote to int. Oops

Replace 'A' with 65 and cast to char

PhiNotPi

02:03

@Dennis just the link above, since the character density didn't seem to match the font, although that may be a local setting.

@ConorO'Brien Comic Papyrus please

Downgoat

(char)(a>=60?74-a/10:70) works :D

Conor O'Brien

that's a thing? ಠ_ಠ

ASCII-only

@Downgoat a>59

@Downgoat Can you give context/more of the code

You may be able to do char foo=a>59?74-a/10:70

Dennis

@PhiNotPi The CSS file just says monospace, so it uses your browser's default, whatever that is.

quartata

@Downgoat Doesn't work for 100 though.

Downgoat

02:06

nobody cares about 100 anyway :P

i have never had grade of 100 anyway

quartata

I think even with a second ternary for that it still would be shorter though

Downgoat

so clearly it is bad test case

quartata

You know you'll get an F for golfing your homework right

Conor O'Brien

that was the prompt tho

ASCII-only

a>59?a>99?65:74-a/10:70

quartata

02:09

@ConorO'Brien ...soo I really just did his homework for him

Conor O'Brien

yup.

quartata

I've broken the golden rule of SE

Damn.

ASCII-only

RIP quartata you're going to be forever exiled from SE now or something

Downgoat

:D tyvm

Conor O'Brien

@quartata I have a quick math question: ~~do my hw~~

Downgoat

02:11

brb pinging quartata for all future HW assignment

ASCII-only

What is with groovy? "Spaceship operator" "Elvis operator"

quartata

@ASCII-only Hey, the Elvis operator is great

And spaceship comes from Perl

Dennis

@ASCII-only charcoal.tryitonline.net/…

Works without input, but it gets mad if I add the -i flag.

Also, what are all those non-ASCII characters doing in your source code, @ASCII-only?

2

I'll just leave the wrapper as canonical as possible so you can add CLAs in any way that's needed.

ASCII-only

02:29

@Dennis Like what

Dmitry Kudriavtsev

Here are some Terminus screenshots

terminus-font.sourceforge.net/shots.html

PhiNotPi

@ASCII-only origin of the spaceship operator name, as retold by the creator himself: groups.google.com/a/dartlang.org/d/msg/misc/WS5xftItpl4/…

ASCII-only

@Dennis What do you mean, that probably means I either broke the encoding or they're part of the AST printer, or syntax because Charcoal uses ASCII almost exclusively for string literals

@Dennis Thanks!

Dennis

@ASCII-only ¶Ｐ×⁸Ｍ⁵↓⁺×⁸¶ＵＢ

(Source code of the example program, not the interpreter.)

ASCII-only

The programs? The same reason, ASCII is used only for strings and multiple directions

Dennis

02:37

Just a pun on your username. :P

ASCII-only

@Dennis Oh, oops, that's a bug - I think I've fixed it, will push once I figure out what the best default charset for compression is

Dennis

OK, just give me a heads-up when I should pull.

ASCII-only

@Dennis Whoops, fixed

Dennis

:P

Maltysen

@Dennis whoa what's your halloween effect, it look so cool

Dennis

02:53

Inverted colors and altered hue/saturation.

Hue 140, sat 70 iirc.

PhiNotPi

My halloween effect is a 360° no-scoped version of my normal avatar.

Dennis

Fond memories of green monochrome monitors.

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