The Nineteenth Byte

Eᴀsᴛᴇʀʟʏ Iʀᴋ

04:00

:D

Alex A.

14 mins ago, by Eᴀsᴛᴇʀʟʏ Iʀᴋ

goodnight now!

So much for that I guess :P

Conor's been a bad influence

Sherlock9

So where in the world have you been, @AlexA.?

Alex A.

Out and about, hither and thither, to and fro

Helka Homba

Out and about?

Sherlock9

Considering the high rate of PPCG members getting married in the past two years (more than 5, I think), I figure I should ask, did you also get married?

Alex A.

04:06

I've just been busy with other things. I've only had time for some administrative modly things

@Sherlock9 Hah, not yet

@HelkaHomba That's what I meant :I

@mınxomaτ That seems like a neat idea. I'd be interested in contributing but as I've said, I've been really busy lately. So you can put me down as "interested but not immediately available."

mınxomaτ

Noted

Alex A.

I like Bayslick's theme better, btw ;)

Also is that your voice in the voiceover?

mınxomaτ

Yep

Alex A.

Foxy ( ͡° ͜ʖ ͡°)

mınxomaτ

I have no idea what that's supposed to mean.

Alex A.

04:13

You have a very podcast-friendly voice

mınxomaτ

Interesting.

Helka Homba

+1 for common sense over partisan politics - assets.documentcloud.org/documents/3007589/…

3

Dennis

@ASCII-only I think you're underestimating how much Tio! is used. Just yesterday (UTC), the backend handled 4493 queries.

mınxomaτ

> how much Tio! is just

Well, an unjust TIO would be bad, I guess.

Alex A.

@HelkaHomba +1 indeed.

Dennis

04:18

7 hours ago, by Geobits

@NathanMerrill if(cookieUser!="Dennis")doShadyStuffToWreckScore();

ASCII-only

@Dennis hmm, can you tell how many are non-website api requests?

Alex A.

@Dennis For real? Holy crap!

@ASCII-only I don't think he set up a public API?

mınxomaτ

Still, a look at the access log would be interesting.

Dennis

@AlexA. I allow CORS, so I don't really have to.

ASCII-only

maybe not, but the graduation script uses an api

Dennis

04:21

@mınxomaτ There's not much to see, as it only logs very basic information for each request.

For example:

<redacted IP> - - [09/Aug/2016:00:18:40 -0400] "POST /cgi-bin/backend HTTP/1.1" 200 381 "http://retina.tryitonline.net/" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.82 Safari/537.36"

@AlexA. Yeah, hence the shortage of RAM.

That could be handled with aggressive caching, but I'd need more disk space then.

Alex A.

ASCII-only

if you could see how many were from ppcg you'd be able to see how well caching would work or something

Sp3000

@Dennis I like to think that a fair portion of that number is phone golfing :P

Feature request though: make TIO always return debug, but not show the debug if debug is off? Not sure how useful that would be, but I find myself doing two requests a lot for debug on then off

Dennis

Maybe. I should add Python soon. Ideone's mobile site is a pain and repl.it is completely unusable from my phone. Although, neither has SymPy, etc.

Sp3000

If I throw money at you would you add an SSL certificate? :P

Dennis

04:30

@Sp3000 Hm, I'd have to find a way to mingle the different streams. It's a good idea either way though, since all output to STDERR ends up in the Apache logs.

@Sp3000 For SSL, I'd have to go with some free option or change the URL format. Wildcard certificates are extremely expensive.

For example, DigiCert takes USD 1070,- for 3 years.

Alex A.

D:

Sp3000

Okay, a tad out of my price range there :P

mınxomaτ

@Sp3000 SSL is free.

Except for company extended validation.

Dennis

Most free options are a big pain for 70+ subdomains though.

The alternative would be to use tryitonline.net/retina instead of retina.tryitonline.net/, but the latter looks much nicer imho.

mınxomaτ

@Dennis One script running letsencrypt for every subdomain. It takes a few seconds to issue a cert per subdomain. I've literally done that.

Dennis

04:36

They have a rate limit though.

mınxomaτ

You can write a few lines of PHP to pass the old requests from lang.@ to @/lang.

One catch-all DNS record pointing to that rewrite script. The apex record pointed to TIO with SSL.

So you don't have to do any additional work when adding a language.

Dennis

Ooh, they let you include up to 100 domain names in a single certificate! That makes it a lot easier.

ASCII-only

@Dennis badnwith is fine right?

;_; why are ipads so hard ot type on

Alex A.

;_; why is it so difficult to proofread before pressing enter

Doorknob

Rust documentation is installed.
std is standing at the ready.
Rust is ready to roll.

I love the Rust installation messages

Alex A.

04:51

Was that using rustup?

Doorknob

No, I just finished compiling it

Cross compiling for my Pi

Alex A.

Oh, okay. I got Rust through Homebrew, so it didn't come with any fun messages

Sherlock9

@HelkaHomba Geez, most of that letter is the signatures. That is a lot of people.

Dennis

05:19

@ASCII-only Bandwidth peeked at 0.2 Mbps in the last seven days.

I also have a transfer cap, but transfer doesn't appear in my logs.

New Main Posts

0

Q: Fraction to exact decimal

Write a program or function that given two integers a, b outputs a string containing a decimal number representing the fraction a/b exactly. If a/b is integer, simply output the value, without a decimal dot or leading zeroes: 123562375921304812375087183597 / 2777 -> 44494913907563850333124661 8...

code-golf

Nathan Merrill

05:40

I'm writing some code that automatically pulls down code from a question for a KoTH. I need to treat Java differently, so I'm thinking of requiring Java submissions to put the word "Java" in their first header

ASCII-only

@NathanMerrill why treat java differently?

Nathan Merrill

speed. The controller is in Java, so making native method calls is much faster

ASCII-only

@AlexA. no, it's really hard to correct

@NathanMerrill yeah but how do you run them if you don't even know the language

Nathan Merrill

ah, if its a different language, then they'll need to provide 2 codeblocks, the first indicating how to run it, the second containing the code

but still unsure on how the second should work

due to filenames

I've historically had a "command.txt", which is all of the terminal commands needed to run the program

ASCII-only

@NathanMerrill then for java make the first codeblock just java

Nathan Merrill

05:43

ew, gross

ASCII-only

then just assume it's java if the first codeblock is left out

Nathan Merrill

but the problem comes when I say "what should the filename of this file be?"

ASCII-only

or detect language via syntax highlighting comments

Nathan Merrill

actually, I could do the comments

make it an either-or

ASCII-only

@NathanMerrill make it the post number?

Nathan Merrill

05:44

no, because the command.txt needs to refer to it

ASCII-only

@NathanMerrill command.txt?

Nathan Merrill

2 mins ago, by Nathan Merrill

I've historically had a "command.txt", which is all of the terminal commands needed to run the program

basically "python3 prog.py"

ASCII-only

but if it's java you're not supposed to have command.txt

Nathan Merrill

right, but simply having 2 code blocks isn't good enough to consider it non-Java IMO

there are plenty of posts that will create 2 code blocks for easy reading or for explanations, or for other things

ASCII-only

@NathanMerrill ?

Nathan Merrill

05:47

nevermind

basically, I need to: 1. Identify if its a Java program (which I think will work with code comments or a Java header), and then 2. Figure out a good way to save the code if it isn't Java

ASCII-only

@NathanMerrill good way to save the code?

Nathan Merrill

aka, what to name the file

ASCII-only

provide that as another HTML comment/a comment in commands.txt?

Nathan Merrill

The problem with HTML comment is it isn't really obvious, which means that every person is going to trying to figure out how to make it work. A comment in commands.txt would work, but it does limit submissions to a single file

ASCII-only

@NathanMerrill how is html comment not obvious

Nathan Merrill

05:53

because comments don't appear in a post?

(to the end user)

ASCII-only

hmm, fair enough

for commands.txt just include a comment with a space-delimited list of filenames, one per codeblock?

Anonymous

@Dennis If you're going to add Python to TIO, how are you going to handle the fact that a whole lot of the language is unsafe for an online interpreter, and there are no working sandboxed implementations?

orlp

hrm

Nathan Merrill

hmmm, that's not a bad idea. It's somewhat obvious for the first one, and easily extended if more are needed

ASCII-only

@Mego Doesn't Dennis run TIO in a sandbox though?

Nathan Merrill

05:55

@Mego I thought he had a sandbox he was already applying to several of the languages

Sp3000

@Mego Probably the same way Julia's being handled atm

orlp

if people comment that your challenge is impossible or if they ask if they can solve an easier challenge (answer: no), I think you've made a good challenge :P

Nathan Merrill

@orlp lol :)

ASCII-only

@orlp like the Quest for Tetris

orlp

1

Q: Fraction to exact decimal

Write a program or function that given two integers a, b outputs a string containing a decimal number representing the fraction a/b exactly. If a/b is integer, simply output the value, without a decimal dot or leading zeroes: 123562375921304812375087183597 / 2777 -> 44494913907563850333124661 8...

code-golf

Dennis

05:56

@Mego I'm using a sandbox for three languages currently. It's a pain to set up because some languages don't play along with it, but I hope that I could get Python to work.

orlp

solving this in a proper way is actually fairly difficult

Nathan Merrill

@orlp Upcoming challenge: P = NP

Anonymous

@Dennis How does it work? Is it a chroot sandbox?

Dennis

More or less. It catches all write access to the file system or any kind of network access.

feersum

@Dennis Maybe you could check what shinh does, he has a golf sandbox for even more languages than TIO.

Nathan Merrill

06:02

@Dennis can you catch spawned threads?

Dennis

Not with the sandbox, but processes are limited.

Nathan Merrill

how so?

Dennis

@feersum Oh, is shinh's code public?

feersum

I think so.

Dennis

@NathanMerrill The OS lets you tweak it.

Nathan Merrill

06:03

github.com/shinh/ags

"I don't mind too much even if a user manages to break my server. It doesn't contain very important information. However, I don't want an attacker to attack another server using my server, even when an attacker manages to be the root user of the backend."

Dennis

That sounds like a sane policy. Restoring Tio! from a backup takes minutes.

orlp

shit

my examples may be incorrect..

my algorithm wasn't accurate yet

my algorithm accurately determines 1/n recurring decimals

but I assumed that a/b would be the same as a * (1/b) modulo however long the repeating decimal part is

Sp3000

I think another example where there's a part before the recurring section begins would be good btw

orlp

but that's not correct because 1/15 = 0.0(6)

but now my algorithm believes 2/15 = 0.1(2)

since 2*6 mod 10 = 2

but it should be 0.1(3)

feersum

@orlp Yep, Mathematica gives a different answer for 235/14.

orlp

06:18

@Sp3000 there is such a case

although not a very big one

Sp3000

I said another...? (preferably with more than one digit)

orlp

ah

@feersum can you give me whatever Mathematica gives for each fraction?

I messed up and just now discovered the bug in my algorithm...

feersum

In[103]:= RealDigits[355 / 113]

Out[103]= {{3, {1, 4, 1, 5, 9, 2, 9, 2, 0, 3, 5, 3, 9, 8, 2, 3, 0, 0, 8, 8, 4, 9, 5, 5, 7, 5, 2, 2, 1, 2, 3,

>      8, 9, 3, 8, 0, 5, 3, 0, 9, 7, 3, 4, 5, 1, 3, 2, 7, 4, 3, 3, 6, 2, 8, 3, 1, 8, 5, 8, 4, 0, 7, 0, 7, 9,

>      6, 4, 6, 0, 1, 7, 6, 9, 9, 1, 1, 5, 0, 4, 4, 2, 4, 7, 7, 8, 7, 6, 1, 0, 6, 1, 9, 4, 6, 9, 0, 2, 6, 5,

>      4, 8, 6, 7, 2, 5, 6, 6, 3, 7, 1, 6, 8}}, 1}

In[104]:= RealDigits[235/14]

Out[104]= {{1, 6, 7, {8, 5, 7, 1, 4, 2}}, 2}

In[105]:= RealDigits[123/321]

@feersum lol great formatting

orlp

so all of mine were correct except 235/14

now I need to find a solution for my bug...

miles

@Zgarb thanks for making me think about that binary conversion some more, I realized that a size 3 infix like _4 0 16 would be 0 when converted to binary which would give an incorrect result

Zgarb

06:33

@miles Would @* somewhere be enough to fix it?

Destructible Watermelon

I actually cracked someones answer in the cops and robbers challenge (I think)!

Sp3000

@orlp Test case for b < 0?

orlp

@Sp3000 3289323463 / -250000000 -> -13.157293852

Sp3000

Ah, right. Missed that one

miles

@Zgarb I think using abs instead of identity at the start might fix it

I think that would let me also using +/ as well as #.

orlp

06:46

nvm, figured out my math

Zgarb

@miles And 0< instead of 0~:

miles

oh yeah that too, since it will always be a positive value from the sublists

well it's been fun, the handle on my toilet broke, so I replaced it, but now the seal broke too so it keeps draining

might as well buy replacement parts for everything else that might break in a row

feersum

Does anyone know the link to download the OEIS?

The only one I could find had only the list of terms and lacked the offsets.

miles

there's a compressed file I was using

it contains the sequence ID and the first few couple terms which is quicker when searching

oeis.org/wiki/Welcome#Compressed_Versions

feersum

What I want is to have the terms and also the offsets (first value for which the function is defined).

miles

07:01

they might not offer one directly, but you could crawl their site and save each, while also being considerate of usage

feersum

lol, I did find where someone put their OEIS scraper code on github

meh, I'll just do without the offsets

How can there be 270000 entries in this thing anyway?

Are there parametrized sequences generated en masse?

Sp3000

"Multiples of X", "Characteristic function of multiples of X", "Multiples of X containing X in their decimal representation"...

feersum

Right, I wonder if they have any policies on how many cases of something like that you can put in.

xnor

how often is the characteristic function of a sequence included?

Sp3000

Quite a lot for simpler sequences, at least?

Rows of triangles is another common transformation

miles

07:14

yeah those triangles, you get central values, diagonals, etc, theres also convolutions of sequences

miles

07:52

@Dennis I have no idea how you got it down to 5 bytes, but I believe I've found an inefficient 8 byte version

muddyfish

26

Q: What is QuadRooter? Are 900 million Android devices vulnerable?

What actually is QuadRooter and how does it work on Android devices? It is currently in the news that 900 millions Android devices are vulnerable: Serious security flaws that could give attackers complete access to a phone's data have been found in software used on tens of millions of Androi...

security stock-android

Also if you don't see me this afternoon, presume I'm in hospital; I have my first driving lesson in 8 hours :O

Destructible Watermelon

Yo!↷¡ºλ

miles

wow way to make us feel old

mınxomaτ

> These are weaknesses in Linux/Android system software provided by chipset manufacturer Qualcomm.

I read this as "weaknesses provided by Qualcomm" :D

muddyfish

My phone's vulnerable :(

mınxomaτ

07:59

Well, if you have an android phone (any) (I have one, too), you are vulnerable to a tremendous amount of creeping security issues. The art is to accept that, educate yourself and oversee countermeasures yourself.

muddyfish

Basically don't store anything sensitive on your phone

orlp

I fixed my code

gist.github.com/orlp/a406dd7fd92dc4714c976276483ad8e1

@Sp3000 ^ that's calculating the recurring decimal without abusing pattern detection

miles

@Sherlock9 thanks for your great interest in that problem

Sherlock9

You're welcome. I still have no idea how that formula works but I think I'm getting close

ASCII-only

@feersum offsets?

Anonymous

08:10

@mınxomaτ Not that far off

mınxomaτ

Technically true even

orlp

I think it's fascinating

how the length of the recurring fraction for a/b is O(b)

Anonymous

256! is a big number

Anonymous

What fresh hell have I thrust upon myself

ASCII-only

@Mego ?

@orlp but chrome is not the best

VTCAKAVSMoACE

08:19

@ConorO'Brien github.com/VTCAKAVSMoACE/webpass

Releasing Helium Nuclei

Hai

VTCAKAVSMoACE

@ReleasingHeliumNuclei hoi

Sherlock9

Hey VTC

VTCAKAVSMoACE

@Sherlock9 ohay Sher

ASCII-only

npm install linux -g

Anonymous

08:22

Gasp it's a Vitsy!

ASCII-only

10/10 best module

VTCAKAVSMoACE

@Mego lol that's my child

Anonymous

Vitsy Sr.

ASCII-only

Vitsy nulla/Vitsy I depending on whether it's 0 or 1-based

VTCAKAVSMoACE

I think I'm gonna give up on Laura (the language) and move to a compiler-based one. What I was attempting to do was basically infeasible.

ASCII-only

08:24

@VTCAKAVSMoACE what were you trying to do?

Anonymous

What was Laura?

ASCII-only

^

Anonymous

(other than your second child)

VTCAKAVSMoACE

@ASCII-only Dynamic forced libraries which could theoretically change syntax or introduce completely new features.

ASCII-only

@VTCAKAVSMoACE Change syntax? Like Tcl?

Sherlock9

08:26

@ASCII-only You may have too much beta-caretene in your diet

VTCAKAVSMoACE

@ASCII-only Imagine that you could be writing in ><> in one program, CJam the next, and Pyth+CJam+><> in the next.

That's kinda what I mean.

ASCII-only

@VTCAKAVSMoACE ven already made that

VTCAKAVSMoACE

@ASCII-only Link.

ASCII-only

@VTCAKAVSMoACE brb, looking for it

VTCAKAVSMoACE

kk

Anonymous

08:27

@VTCAKAVSMoACE Sounds like what DataBot 2.0 was supposed to be :P

VTCAKAVSMoACE

@Mego Yeah, it was kinda inspired by that. :P

Anonymous

I still want to finish the multitool interpreter :P

ASCII-only

0

A: What programming languages have been created by PPCG users?

∀ ∀ (or "forall") is a language that piggy-backs on other golfing language to build a golf pipeline. Not sure whether to use Perl 5, Jelly, Retina or Pyth for some challenge? Why not use all three together? See it on Github. This is an example ∀ program: y+ pVsQN r(\d+) r$*# r!`#+ nsay join ...

Only 4 languages right now though

VTCAKAVSMoACE

We should look into getting a consistent serverspace for Databot.

@ASCII-only Hmm. That's not entirely what I mean.

Anonymous

I have a Linux server running out of my spare bedroom/office

Anonymous

08:28

I'm just not sure about the stability

ASCII-only

@VTCAKAVSMoACE I know, but extremely extensible syntax is really hard

VTCAKAVSMoACE

The functionality would remain, but the syntax would be assigned according to what characters were available, so you could mix/match it easily. It would be compiled into the multiple languages rather than scripted between them.

@Mego I've got one too, same issue.

To be fair, I don't think I've done much with my RPi and it rarely goes down.

ASCII-only

You probably need to compile the syntax to a bison/ANTLR (basically any syntax compiler) syntax to create the parser

Anonymous

Mine is an old Dell server tower that my grandfather-in-law gave me :P

TùxCräftîñg

hi

ASCII-only

08:31

@VTCAKAVSMoACE what characters were available?

VTCAKAVSMoACE

@ASCII-only Not really. Just write it in the original languages and make a descriptor of langs in a .conf.

@ASCII-only UTF-8.

ASCII-only

so it's similar to ven's, just transpiling the encoding?

VTCAKAVSMoACE

@ASCII-only Yeah, so you don't have to use two extra characters whenever you change languages. Unionous rather than split up into chunks and then pasted together.

@ASCII-only The other problem is that I was also thinking of providing language tweaks along with it, and I tried to do too much at once and the lang is basically unusable for now.

ASCII-only

@VTCAKAVSMoACE language tweaks?

VTCAKAVSMoACE

I'll probably come back to it.

@ASCII-only So, for example, allowing calls to the host language (Java) directly for use of libraries like graphics and such.

ASCII-only

08:37

@VTCAKAVSMoACE shouldn't you make the graphics libraries golfy as well?

@VTCAKAVSMoACE unionous?

VTCAKAVSMoACE

@ASCII-only Yes, their calls would be shortened as well.

@ASCII-only So you could use them inside parts of other languages, as well as separately. Think of it like evaluating each chunk of code where the evaluation is recursive.

ASCII-only

oh wait I've seen that somewhere

VTCAKAVSMoACE

Regardless, though, I'll come back to Laura later. Just too complex for me to work out right now, I'm leaving the whiteboard with my plans on it unerased.

ASCII-only

cs.nyu.edu/rgrimm/xtc/jeannie.html

scroll to 1.2

Geobits

Oh good lord

 `.C {                                      // 1
 #include <stdio.h>                         // 2
 }                                          // 3
 class Main {                               // 4
   public static void main(String[] args) { // 5
     `printf("Hello, world!\n");            // 6
   }                                        // 7
 }

zyabin101

08:46

Hello

Geobits

That's just plain evil.

Anonymous

I'm not sure what I'm reading but I don't think I like it

Destructible Watermelon

> The following Jeannie program (integration test 041) has a Java main method that uses a nested C call to print "Hello, world!" to the console

TùxCräftîñg

@Geobits ಠ_ಠ

Geobits

Hey, I didn't write it. I'm just as appalled as the rest of you.

VTCAKAVSMoACE

08:50

@ASCII-only Just about, but with the esolangs.

Anonymous

That's disgusting

Anonymous

C and Java should not mix like that

ASCII-only

Yeah, I know

but for esolangs it should be perfectly fine

Anonymous

It's like adding soap to coffee. Both have their separate uses, but why would anyone want to combine them?

7

Geobits

Isn't that called a foam latte?

Anonymous

08:52

@Geobits You crazy Floridians and your nonsense drinks

Destructible Watermelon

isn't C# like java and C anyway?

VTCAKAVSMoACE

@Mego lol oddly accurate because java means coffee

Anonymous

@VTCAKAVSMoACE And after using C, you want nothing more than a hot shower, with nice scented soap, and a ball of steel wool to scrub yourself really clean.

3

Geobits

@DestructibleWatermelon C# is more like a demon let loose from the fourth circle of hell.

2

Destructible Watermelon

Also apparently coffee soap exists

Anonymous

08:55

@Geobits I'm pretty sure C# is one of the demons in Diablo

ASCII-only

@Geobits fourth circle is not so bad

Destructible Watermelon

@Geobits I'm definitely going to quote this to my C# friend

ASCII-only

I guess the fourth circle must still be horrible though

Geobits

ping ping ping

ASCII-only

used to use C#

DJMcMayhem

08:56

Hey! I kinda like D-flat.

TùxCräftîñg

strawpoll.me/10950955

Geobits

D-flat is okay. C-sharp is where the problem is :P

ASCII-only

It's like java but slightly less verbose, slightly better and forces you to use OOP slightly less, and has slightly better dynamic runtime support

TùxCräftîñg

Java is worse than C#

^^

Geobits

Slightly less verbose? Not that I've ever seen.

DJMcMayhem

08:57

Why are all languages designed with straw polls now?

ASCII-only

@Geobits it has : instead of extends/inherits and is instead of instanceof

that's pretty much it though

Geobits

@DJMcMayhem Because people have stopped making decisions for themselves now.

DJMcMayhem

I'm going to make a language where literally every single design decision is decided with a straw poll.

Geobits

Did you decide that yourself???

TùxCräftîñg

^

Destructible Watermelon

08:59

Strawpoll whether you should strawpoll the strawpoll

DJMcMayhem

@Geobits strawpoll.me/10950968

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