The Nineteenth Byte

Thomas Kwa

00:06

@PhiNotPi Me!

I read every page intently several times.

Including the extension about computers.

PhiNotPi

Yeah, I have the computer extension too.

Thomas Kwa

@PhiNotPi When were you in elementary school?

PhiNotPi

This would probably be a little over 10 years ago.

I also have this book: amazon.com/The-Usborne-Internet-Linked-Science-Encyclopedia/dp/…

Cᴏɴᴏʀ O'Bʀɪᴇɴ

Then, I look to the right to see that my message has 5 stars, and realize I can die happy. XD

quartata

00:27

I'm back.

Cᴏɴᴏʀ O'Bʀɪᴇɴ

wb

quartata

I see I missed Doorknob's plea for help

APL syntax and symbols

The APL programming language is distinctive in being symbolic rather than lexical: its primitives are denoted by symbols, not words. These symbols were originally devised as a mathematical notation. APL programmers often assign informal names when discussing functions and operators (for example, product for ×/) but the core functions and operators provided by the language are denoted by non-textual symbols. == Monadic and dyadic functionsEdit == Most symbols denote functions or operators. A monadic function takes as its argument the result of evaluating everything to its right. (Moderated in the...

So how exactly are you supposed to type APL symbols?

And what's the best current APL implementation? I'm going to try to learn a bit of it.

Cᴏɴᴏʀ O'Bʀɪᴇɴ

XD You copy them or use an APL keybaord it

quartata

Hmm

I think I'll have more fun learning binary lambda calculus.

I want to learn APL, but if I can't type it then I'm not sure what to do.

Maybe I should make an APL compiler that compiles mnemonics into actual APL code.

In fact, I'm sure someone has done that...

question eligible for bounty in 33 minutes

༼ つ ◕_◕ ༽つ

Cᴏɴᴏʀ O'Bʀɪᴇɴ

xD

Thomas Kwa

00:37

@quartata what question?

quartata

RTTTL Obfuscation

Daniel M.

That will be interesting

quartata

It's very interesting.

Too bad it doesn't have very many answers.

Honestly, I was kinda hoping to get quite a few answers. It would have been neat to see a lot of different obfuscation techniques.

Daniel M.

Yeah, the problem is that most languages just can't work

quartata

Plus pop-con really works the best with lots of answers :P

@DanielM. Yeah, sadly.

I thought maybe it would be somewhat easier due to the sharp notes, which are comments in most languages.

quartata

01:03

I have a sudden, overwhelming urge to make a challenge involving Pan Galactic Gargle Blasters.

I have no idea what it would be about, just that it needs to contain the words "Pan Galactic Gargle Blaster."

Cᴏɴᴏʀ O'Bʀɪᴇɴ

01:26

xD

El'endia Starman

@Sp3000 That would work. However, Befunge doesn't have l and Minkolang doesn't have an equivalent yet.

I'm pretty convinced that a language without stack manipulation is not Turing-complete.

Sp3000

An expensive way would be to keep track of the length of stack manually (actually it probably wouldn't be too bad in Befunge-98, with k)

Actually, why are you doing this by building up the stack again?

(as opposed to multiplying as you go)

El'endia Starman

02:25

No stack manipulation or reflection capabilities.

Sp3000

1&> v
1-^>:00p*00g
$.@^_

Hmm p/g is expensive

PhiNotPi

It's starting to look good: koth-phinotpi.rhcloud.com

El'endia Starman

p/g is what I mean by "reflection".

Sp3000

Ah, k

New Main Posts

02:42

0

Q: The Mystery String Printer (Cops)

The robbers thread can be found here: The Mystery String Printer (Robbers) Your challenge Write a complete program that prints a string to STDOUT. The robbers will try to create a program that prints the same string. If they successfully can create the program within 7 days, your submission is...

cops-and-robbers

0

Q: The Mystery String Printer (Robbers)

The cops thread can be found here: The Mystery String Printer (Cops) Your challenge Choose a submission from the cops thread, and print out the string from an answer in that thread. The submission that you choose must not be safe (it must be newer than 7 days). Your program needs to follow the...

cops-and-robbers

Daniel M.

Oh wow, that bot is fast

quartata

I think I've got everything I want to put in Downdraft.

Here's a program for this challenge: codegolf.stackexchange.com/questions/57802/…

Contains unprintables.

It's 65 bytes which isn't actually that good...

Oh oops I just noticed that I didn't escape the backquotes

Huh, I guess you just can't have backquotes.

pastebin.com/8RsVMjjk

Better

It'll be tricky to implement all the features I used in that program. I'm going to work up to it, and once it can run that program I'll release it. Then I'll try to think of ways to make it better for golfing.

Thomas Kwa

02:57

Are we allowed to use cryptographic hash functions in cops-and-robbers challenges?

PhiNotPi

^ really should be disallowed, as standard CnR practice

Sp3000

Should probably post a comment

Daniel M.

The key must be between 0 and 255

Because it acts pretty much like a pseudo-random number generator

Daniel M.

03:13

@ThomasKwa I don't speak pyth, so what is being used as the input for the hash in the comment?

Dennis

@Sp3000 It took me a while, a reordering of the strings and base 380 to get it working, but it ultimately saved a byte. Thanks!

Sp3000

Oh? :o nice

Dennis

@DanielM. Cryptographic hash functions are not seeded random calls, so it doesn't matter. They may be similar in many aspects, but the question does not forbid them in its current state.

(The input is the string hl0|VH]Sw<(%<.)

Daniel M.

I'll modify the question so that it treats cryptography like rng's- an input of 1 byte is a bit easier to crack

Dennis

Personally, I'd simply forbid all built-ins that involve cryptographic primitives (PRNGs, encryption/decryption, cryptographic hash functions, etc.).

DankMemes

03:26

^

Daniel M.

Ok, changed it

Sp3000

03:45

You know, I've never figured out how to use Stuck's interpreter (pretty sure the cop's easy though)

Daniel M.

That's why the program lengths where the cop is really easy give much less points. The robbers are going to have a real tough time, though.

Daniel M.

03:58

Well anyways, it's midnight here, so I'll be checking out

Sp3000

04:19

@Tryth Fun fact: The one I was going to post was indeed STDOUT redirection :P (but thanks for clarifying)

Tryth

@Sp3000 It appears I might have made a mistake. My REPL is giving me a different output to my commandline. Deleting it until I can work out what has happened. Apologies :P

Sp3000

Ah :P

For reference I have 103 bytes over here, so...

PhiNotPi

I'm about to make a meta post about my PPCG server

Tryth

Ah. I see what has happened. Looks like my 47 byte thingamajig might be invalid

It's because the __import__('this') only activates once in the REPL

Sp3000

:( damn

New Meta Posts

04:49

0

Q: Introducing a KOTH server!

The Motivation The desire for a KOTH server has been around for a while. There have been a couple notable meta discussions about it in the past: Creating an official place to become a King of the Hill tester How could we run KotHs in a distributed fashion? By being able to host KOTHs on a se...

discussion

El'endia Starman

05:21

I now have for loops in Minkolang! The full program for calculating a factorial is thus: 1n[i1+*]N. . :D

Sp3000

Dennis' one is actually a fun puzzle and not just number bashing for once :D

Dennis

Which one? :P

Sp3000

The Pyth one

(having said that, number strings win too much :( )

Sp3000

05:58

Darn, this shouldn't be that hard but it is :P

Dennis

@BetaDecay 32 bytes? Why so mean? :P

Beta Decay

06:19

@Dennis I'll give you a clue: It's a variant of something that all mathematicians and programmers know and love ;)

And I didn't realise that it was that long until I measured it :P

Sp3000

Damnit Dennis do you need that many number strings? :P

xnor

how should someone post a mathematical proof here?

this is for this answer: codegolf.stackexchange.com/a/60286/20260

SE doesn't like answers where the content is in the link, but MathJax is not enabled here

Sp3000

06:35

Okay I think I've got Dennis', but I don't know Pyth well enough. Drat.

Sp3000

06:47

Hmm how does one take a list product in Pyth...

xnor

07:19

argh, I feel like this CnR, like so many before it, is a good idea spoiled by a whole lot of needless rules

not letting me submit multiple cops in one language

letting someone crack it in a more concise language

requiring the length to be given to a nearest power of 2, so I can't use a clever 5-byte code

requiring it to be a full program so that Python has to have a print and Haskell has to include ugly IO

Sp3000

Unfortunately, yeah :( I didn't read the crack-in-other-language part, or Stuck would have gone down even quicker

With Pyth there, it makes Python a bit harder

xnor

yup

especially because print plus anything interesting takes you over 8 bytes to 16 bytes, where Pyth can do basically anything

Peter Taylor

Informal poll: would anyone die of a heart attack if I posted a popcon to the sandbox?

xnor

what happened to the real Peter Taylor?

Sp3000

You may or may not get instant upvotes and be showered with stars and love

Peter Taylor

07:22

He came back from holiday with some panoramic photos that, when stitched, have holes that need filling in the sky.

xnor

it's a doppelganger!

the real Peter Taylor is locked up somewhere

Peter Taylor

And since judging how well they're filled is better done by people than by any program I care to write, I wondered about making it into a popcon.

xnor

i take it you'd ban image libraries that stitch or fill for you?

Peter Taylor

Are there any?

Sp3000

from adobe.photoshop import content_aware <-- I wish

Peter Taylor

07:25

The stitching isn't the issue. The idea is that I'd provide some stitched images as references. The challenge is basically "extrapolate blue sky colour", which is a lot less trivial than it sounds.

xnor

i think photoshop does have that, though probably not in library form

Beta Decay

@PeterTaylor Paintshop Pro uses Python as its scripting language

Peter Taylor

@BetaDecay So does the GIMP, but I don't think either of them has built-in sky extrapolation.

It's quite a difficult challenge.

xnor

@Sp3000 nicely cracked!

Sp3000

The hardest part was trying to figure out what stringify was in Pyth :P

xnor

07:38

that was also the hardest part of writing it

Sp3000

But yeah the one-per-language rule is pretty annoying too

Now you can't Pyth :/

xnor

yeah

Sp3000

(I guess it stops people from, er, spamming long numbers in CJam or something? But still...)

Beta Decay

What a stupid rule that is

xnor

go complain in the comments

i think the intent is just for scoring

surely there's no problem submitting more for fun

Sp3000

07:48

@BetaDecay I think I've got yours, but I think it's sad if I cracked it in CJam :/

Beta Decay

@Sp3000 Really? Well you can crack if you want, I don't mind :)

Sp3000

Hmm Fourier takes code from STDIN o_O

1~x0~y0~q18(y~z+x~yz~xoq^~q) This is too long and I'm not even done yet

... oh right

Beta Decay

Variables are autoinitialised to 0, so you can have q instead of 0~q BTW

Sp3000

08:04

k :P

randomra

0.675640430319848J0.8376870144941628 I know I have seen this number posted before here, but can't recall where...

Beta Decay

@Sp3000 Nice :D

The actual code was: 1~y^~x20~k(xoy*x~gy~xg~yi^~i) but you are pretty much there

ಠ_ಠ

08:43

@AlexA. status-alex-a.

Optimizer

status-sock-puppets

ಠ_ಠ

status-socks-stink

Optimizer

09:15

status-ಠ_ಠ-is-sock-of-alex-a

New Meta Posts

0

Q: What does "taking no input" mean for a program?

Fixed output challenges usually state that the program "must take no input". I usually interpret this as "The standard input is empty", but after thinking about this, there are actually several valid interpretations: The program has to ignore the standard input, that is, it should work regardle...

discussion policy rules

Mauris

hmmm... Not really a huge fan of the new Cops & Robbers

It's essentially even more impossible than the edit distance one for short APL answers

Martin Büttner

09:40

the fact that you don't have to use the same language really breaks the challenge

New Main Posts

10:22

0

Q: print difference between icmp timestamp in request/reply ping

The challenge involves printing the difference between ICMP originate and receive timestamps. The idea is being able to determine which asymmetric internet path is responsible for packet delay. One can use hping with --icmp-ts option to gain the raw data. The task is complicated by the fact th...

New Sandboxed Posts

11:19

0

A: Sandbox for Proposed Challenges

Ceylon golfer (whitespace + comment removal) As some people might have noted, I'm answering here often using Ceylon. This is usually done first writing a "normal" program, then slimming it down using whichever tricks I find, and at the last step remove all superfluous white space (and possibly a...

0

A: Sandbox for Proposed Challenges

Something smells Fishy... popularity-contestkolmogorov-complexity I recently saw this code in ><>, and it really got me thinking... Your task is to create a program (in any language) that will accept an input of some words and print out a ><> program that writes the same words that were input ...

VTCAKAVSMoACE

11:45

@MartinBüttner Agreed. They should be able to find the solution with the same language, because then you might have a case of exactly the same code or even a golfed answer.

Sp3000

It's why I went and downloaded Fourier anyway :P

VTCAKAVSMoACE

@Sp3000 Is my latest sandbox post similar to anything done before/could you suggest a search term?

I couldn't think of a search to use.

Sp3000

I was going to ask why 3 reflectors actually

I don't think there's been a challenge involving outputting ><> programs before, but I might be wrong

VTCAKAVSMoACE

It makes it just that little bit more complex. I think it'd be cool to see how complex some answers can get.

Sp3000

Also the 8* limit also seems arbitrary. Both of these are trivial to bypass with useless code

VTCAKAVSMoACE

11:52

Are you suggesting I remove them for conciseness?

Sp3000

Well I'm just trying to see what you're trying to do - you've also got this as popcon, so what do you see as a "good" answer?

btw regardless of what you end up doing, it might be good to link to the esolangs page and give a quick description of the language, since not everyone might know what ><> is

VTCAKAVSMoACE

A good answer would be something that might have it so that it outputs code that doesn't repeat itself (for example, H shouldn't be represented as 89* twice). The ><> code should be extremely complex, too, with reflectors everywhere just scattering information. A good output would be similar to the example I put in there.

I'll put those links and description in.

Should I provide a simple description of how to program in ><>, or leave that to the wiki? I'm biased towards the latter.

Sp3000

You can leave it to the wiki if you want, but at least mention 2D/toroidal so people have a basic understand

I still don't get what you mean by "complex" though - why aim for complex?

VTCAKAVSMoACE

Because the program shouldn't just be a simple "this is the best way to do it" output, but rather a more artistic (~~maybe less~~ definitely less efficient) approach.

D: Strikethrough doesn't work?

Sp3000

12:08

Triple hyphen

VTCAKAVSMoACE

There we go.

Should I add a tag similar to art in there?

That tag doesn't exist, or anything similar, but that's what I mean.

Sp3000

Probably not, it'd be a confusing use of the tag compared to what people might expect

@xnor "You all have impressed me before." I almost want to say "bring it on" but ouch complex numbers really hurt

quartata

12:29

Rather ashamed of how fast my stuff got cracked...

I'mma try harder this time.

Sp3000

Trust me, if your cop is a large number that's not too big the first thing I'm doing is shoving it in Wolfram|Alpha :P

quartata

This one won't be a number.

I hope you know your Java because you'll need it.

Sp3000

I don't, so I'll leave it for someone else thanks :)

quartata

0

A: The Mystery String Printer (Cops)

Groovy Range <= 128 String: [class org.codehaus.groovy.tools.GroovyStarter, class org.codehaus.groovy.tools.RootLoader, class org.codehaus.groovy.tools.LoaderConfiguration] This should do much better ;)

mwahahahaha

randomra

@quartata that could be compressed in 128 bytes

quartata

12:45

But only ASCII characters can be in the robbers program

Otherwise Dennis would have cracked every answer with Bubblegum

No, sadly you must find the real way to print it.

Sp3000

You could still do c="class org.codehaus.groovy.tools." then print "["+c+...

randomra

ascii is enough, even printable ascii

quartata

Seriously?

Ugh.

Sp3000

CJam

quartata

Fair enough.

It would have been better in Java rather than Groovy anyways.

One second.

quartata

13:10

Well not only was it incredibly long the Java version claims that the only class it ever loaded was itself.

(It's not like I used a million other classes to get it working or anything)

Hmph

Sp3000

@muddyfish In case you're wondering, the only reason I'm asking is because I was thinking of doing one using __docs__, but refrained because most of them depend on which version you're running

quartata

Does anyone here have MATLAB?

I think I cracked Tom's answer but I can't test it.

aditsu

@PeterTaylor there's a resynthesizer plugin for GIMP

muddyfish

13:32

@Sp3000 the program should print the same stuff from 2.3 to 2.7.9

Sp3000

Is that by research or by testing?

muddyfish

research, I can't find a 2.3 installer

Sp3000

Hmm k (they're all here btw python.org/downloads)

muddyfish

It most certainly works from 2.5 to 2.7.9

Sp3000

tbh I probably won't get around to it though, due to the (I'm guessing) research required

muddyfish

13:36

lol ok

Sp3000

Yeah, I'm only trying to crack ones which look doable without a ton of brute force :P (it's so easy to write a hard cop in this challenge it kinda takes the fun out of it)

muddyfish

Yeah, I can imagine that my one would take quite a lot of force but im pretty sure that my one is possible once you know how to get started (and the second output really makes it easy if you know what to look for)

Martin Büttner

14:16

@Calvin'sHobbies The wall at my new place would make a nice (advanced) sequel for Computer Generated Textured Wall Paint (if there had been any participation to speak of in the original challenge)

Calvin's Hobbies

14:29

@MartinBüttner Funny you mention that. I was thinking the other day about making another similar challenge involving this faux granite pattern

Martin Büttner

wow, that looks even tougher

Calvin's Hobbies

Yeah, and it's not as bright and pretty

@AlexA. What's your favorite integer from 3 to 12?

Martin Büttner

(Hint: there is only one correct answer.)

PhiNotPi

42

Sp3000

It's 10 (base 142857)

Martin Büttner

14:42

(both wrong)

Sweet, Mathematica 10.2 added MixedRadix for base conversion.

Calvin's Hobbies

How are these tasks looking for you pyth/cjam experts?

Martin Büttner

the first two might be below the average of 11.67 in CJam. not sure about the third.

Sp3000

#1) Any rules on the size of the input? (in case any submission uses a hypotenuse function with precision problems) #2) Already tried :P #3) Might be decently longer than average

Calvin's Hobbies

@Sp3000 I'll limit the ints to 2^16

Martin Büttner

I get 9 for the first task, or 8 if I can take input in list form

Sp3000

14:50

tbh, I'm slightly concerned that this might have the same problems as golf practice, in the sense that there's a lot of parts and you can't tell if someone copied or found it of their own accord

Calvin's Hobbies

Yeah, well, that can't be helped can it?

Martin Büttner

"or (ideally) 14 programs" should probably read 12?

Calvin's Hobbies

Yep, thanks

@Sp3000 How would hypotenuse-something help? It's not asking for right triangles.

Martin Büttner

"0200000 should become 2" why doesn't it just remain 200000?

Calvin's Hobbies

@MartinBüttner Because I'm wrong

Sp3000

14:54

... misread, nvm (I get 8 as well for #1)

Martin Büttner

anyway, I get 15 for #2

Sp3000

Just checked, had 14 with leading zeroes, 15 without

(Waits for Martin to try the scary-looking #3)

Martin Büttner

yyeeaah

looks easier in Retina :D

(still way of above average though)

Sp3000

btw are escaped codes allowed for #3?

(I dunno if there's any to move cursor left/right though)

Calvin's Hobbies

Mmm, probly no

muddyfish

15:04

There are codes for moving the cursor in every direction

Martin Büttner

but they'd probably overwrite what's already there

(e.g. backspace for moving to the left)

wat... e& and e| only pop the condition if the block is executed? if anything, I feel like the opposite would make sense

@Sp3000 first working version has 50 bytes

I think this would be a really decent individual challenge

Sp3000

e& with a block sounds really weird for some reason :P

Martin Büttner

oh wait

Sp3000

Decent individual challenge indeed

Martin Büttner

I wanted & and |

Sp3000

15:15

(I didn't even know you could e& with a block - nice :P)

Martin Büttner

46 bytes

Calvin's Hobbies

~50 bytes for task 3? hmm..

Sp3000

{;}e| <-- remove the top two elements if the top element is truthy? I dunno :P (trying to find uses)

Martin Büttner

45

Sp3000

(Bets are you/Dennis have already used it somewhere before though)

Martin Büttner

15:18

no I haven't, I was just being stupid and mixing up {}| and {}e|

Sp3000

The fact that it weirdly keeps the condition is pretty cool though

Martin Büttner

have you tried #3?

Sp3000

Nope, I can't think of a non-painful way to do it

Martin Büttner

LLq{_i32%27>{'=>_)$\[{)@+\}{\(@\+}]=&}{+}?}/\

the space is annoying... otherwise I could do 31/ instead of 32%27> plus '=>

(and distinguish all three cases immediately)

trying to get rid of the awkward [{...}{...}]=& is one byte longer on the first attempt:

LLq{_i32%27>{'=>{1$1<+\1>\}{_W>@+\W<}?}{+}?}/\

Sp3000

Ah, you're keeping track of the left/right halves separately, nice :)

(also incoming HNQ woes)

Calvin's Hobbies

15:32

HNQ woes?

Sp3000

Both halves of mystery string are high up in HNQ

(Doorknob's trying to make us all install Rust)

Martin Büttner

@Sp3000 managed to shorten the switch between arrows and literal characters by 2 bytes

Sp3000

Oh?

Martin Büttner

_'=-z(

this would actually be simpler (not shorter) in Labyrinth :D

Sp3000

Probably simpler for ><> too, with g/p

(again not shorter)

Martin Büttner

15:43

So yeah, I'd definitely support this being a separate challenge ;)

(@Calvin'sHobbies hint hint)

Sp3000

Ditto, definitely too long for the pile :)

Calvin's Hobbies

We'll see

Martin Büttner

@Sp3000 maybe not that (if it remains one of the harder ones), but I'd like to tackle it in some languages which I definitely won't enter into the tweet challenge

Sp3000

I take it the point is not to let people get all of them then? :P

Calvin's Hobbies

I was thinking of making just one of the < or >'s required. Like you can choose which to support.

VTCAKAVSMoACE

15:48

@Doorknob I need a little help with Macaroni. c:

Martin Büttner

@Calvin'sHobbies I'll support just > ;)

Calvin's Hobbies

Oh wait :P

Martin Büttner

if you reduce it to < it would already shorten my code quite a lot though

Sp3000

Ditto Macaroni help, how to Rust

(Specifically: error: can't find crate for `macaroni_lang`)

Martin Büttner

@Calvin'sHobbies first attempt at FILTHE is 29 bytes

Calvin's Hobbies

15:52

k

Martin Büttner

28

Sp3000

nvm got it (cargo build/cargo run it seems)

Martin Büttner

27

ah nice, 24

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