The Nineteenth Byte

TanMath

9:09 PM

IQ[1]=="H""2CH4+4O2>4H2O+2CO2";E O=*int(i[1]) 3 +1;C=*int(i[1]) 2;print"2"+i+" + "+str(O)+"O2"+" > "+i[3]+"H2O"+ " + "+str(CO2)+"CO2"

VoteToClose

Yay! I have a Java answer for that question now!

TanMath

this is pyth code translation of my Python answer...

what is wrong with it?

@Dennis

VoteToClose

@TanMath How does your code handle the input CH4?

Or the input C12H26?

Dennis

@TanMath That doesn't look at all like Pyth code.

TanMath

@Dennis the if statement

Adriandmen

9:14 PM

@TanMath, in Pyth, indexes are handled by @Q1, which is lookup(Q, 1). Q[1] is invalid in Pyth

TanMath

@Adriandmen oh...

Dennis

So are int, str and print.

TanMath

@Dennis oops, the print is messed up...

@Dennis how do you do int and str in pyth?

VoteToClose

@TanMath I think your code is a bit borked... Doesn't work in Ideone.

Oh, it's because you didn't change the second call of the variable CO2. :P

TanMath

wait. what? it was working before

VoteToClose

9:18 PM

..." + "+str(CO2)+"CO2"...

You need to change CO2 to just O.

Dennis

@TanMath I'm hardly a Pyth expert. There s no int AFAIK, but you can use v (eval). Backtick is Python's repr which may or may not have like str (I have no clue).

TanMath

oh.. my code doesn't work...

VoteToClose

Just changing CO2 to O fixes it.

Calvin's Hobbies

5 mins ago, by VoteToClose

You need to change CO2 to just O.

VoteToClose

Can I leave a suggested edit even with the power of mod-editing?

Calvin's Hobbies

9:25 PM

The byte count is also wrong

VoteToClose

^ This is true.

Alex A.

@VoteToClose huhwhat i heard mod

VoteToClose

XD I was just wondering if I can leave suggested edits even though I insta-edit.

Calvin's Hobbies

@VoteToClose I say don't fix peoples problems for them. (Though hypocritically I did fix up the Paris flag challenge, but that wasn't really for the benefit of the user.)

VoteToClose

I was mainly thinking changing the byte count. XD

If he hasn't taken my suggestion to fix the problem with CO2 yet, let him have it. xD

Dennis

9:28 PM

@VoteToClose If you propose the edit from an incognito window, yes. Otherwise, no.

Alex A.

@VoteToClose The inconsistency with which you use "XD" versus "xD" confuses me.

VoteToClose

@AlexA. XD is different from xD in that XD is more of a laugh for the sake of laughing, whilst a xD is more natural.

Calvin's Hobbies

@AlexA. Maybe XD are his real life initials and he's signing the message

Alex A.

No, I know his real life initials. It was part of his explanation of his VTCdsfajasdf username in Minecraft.

VoteToClose

You caught me. ¯\_(ツ)_/¯ I'm Xavier Donald. (not really, obvious sarcasm is obvious)

Ugh. I hate how they lock in votes.

I'm an idiot

Doorknob

9:38 PM

hey, @quartata, Perl is blowing my mind

:P

TimmyD

@Calvin'sHobbies Paris has a flag? /s

Alex A.

@Doorknob In a good way?

Doorknob

yes

Alex A.

Or its wretchedness is blowing your mind?

Oh noooo

Doorknob

:D

Alex A.

9:40 PM

What do you like about it?

quartata

@Doorknob \o/

Doorknob

the idea of scalar vs. list context is really interesting (and powerful)

xnor

for the alkane challenge, I wonder if there's some insane way to extract the number n from int(input(),36)

VoteToClose

Hmm. Question: can we treat command line arguments as STDIN? My guess is no, but... just in case.

Doorknob

it's also similarish to Ruby in syntax which makes my inner Rubyist happy :P

quartata

9:42 PM

@VoteToClose Yes, it is an acceptable alternative to STDIN

TanMath

@VoteToClose which CO2?

Doorknob

also, _ variables are magic

quartata

@Doorknob See? I told you if you like Ruby you'd like Perl

@Doorknob Yes they are.

VoteToClose

24 mins ago, by VoteToClose

..." + "+str(CO2)+"CO2"...

quartata

Nothing makes me happier than being able to just type pop

Alex A.

9:42 PM

@Doorknob Uh what? I don't see any similarities. (Granted, I haven't looked into Ruby much.)

quartata

There's a lesson to be had here.

alex-is-wrong

TanMath

@VoteToClose you mean str(O)?

Doorknob

@quartata haha

VoteToClose

@TanMath Correct.

quartata

27

A: Default for Code Golf: Input/Output methods

Programs may take input via command-line arguments

TanMath

9:45 PM

@VoteToClose so there is no point for C=2*int(i[1])

VoteToClose

o-o Which Python version?

TanMath

@VoteToClose python 2

TimmyD

@TanMath I count 155 Bytes

VoteToClose

/me head desks.

Please ignore me for all time. c: I'm an idiot

quartata

@VoteToClose there can be only one

2

TanMath

9:48 PM

@VoteToClose so all the code is messed up?!

VoteToClose

@quartata The question is... who's the real highlander.

Alex A.

Me

VoteToClose

@TanMath You might need to replace O with C now, but it's your code. ¯\_(ツ)_/¯ I don't really know. What I do know is that it wasn't even running before the change.

quartata

7 mins ago, by quartata

alex-is-wrong

Alex A.

:(

TimmyD

9:51 PM

Highlander, Riga, Republic of Latvia

70 6

quartata

@AlexA. That made me feel bad. I'm sorry.

TanMath

@VoteToClose yeah. i checked cases where H was below 10 but forogt to take into account when it was above 10

quartata

Allow me to rephrase.

VoteToClose

@TimmyD -.-

undergroundmonorail

@VoteToClose If the question says "input", you can use whatever you like from the Meta post @quartata posted. "Back to the chemistry class" specifically requires STDIN.

quartata

9:51 PM

47

Q: Alex is sometimes right

This challenge is to lift the spirits of our mod Alex A., who is usually wrong. Suppose you have a friend named Alex who needs help with basic logic and math, specifically mathematical equivalence. He gives you a list of equations of the form [variable] = [variable] where a [variable] is alwa...

code-golf math logic

That's better.

Alex A.

:)

VoteToClose

> or the nearest equivalent if not possible.

Interpretation. I'll ask the OP, but I'm pretty sure that means I can use CLAs.

quartata

> if not possible

TimmyD

> possible

quartata

> si pas possible

VoteToClose

9:52 PM

> nearest equivalent

undergroundmonorail

Java can use STDIN, so it must. If there was no way for Java to use STDIN you'd be allowed to use command line arguments.

Doorknob

>

2

quartata

@undergroundmonorail Does barely being able to use it count?

Doorknob

@undergroundmonorail If there were no way! :P

undergroundmonorail

@quartata unfortunately i think if you can at all, you have to

@Doorknob thanks, mom

Doorknob

9:54 PM

no that's Martin

VoteToClose

@undergroundmonorail I can't use it. XD I've never used STDIN before, actually. XD

undergroundmonorail

/me does a sick kickflip

Alex A.

@Doorknob Momtin and Dadknob

5

Doorknob

You can be Aunt Alex :P

Alex A.

ಠ_ಠ

quartata

9:55 PM

@Doorknob What about me and Dennis?

What are we?

Alex A.

@quartata Ahem, the mods are the parents.

quartata

@AlexA. OK, you're still excluding Dennis and gnibbler.

fix it

VoteToClose

@quartata Dirty cousins?

XD I joke.

Alex A.

ew wth

TimmyD

@quartata qurazy qusin quartata

quartata

9:56 PM

I was thinking gnibbler could be like the mute grandfather

But I don't know what Dennis is.

Maybe annoying next-door neighbor?

Alex A.

I mod-veto "Aunt Alex." What are Dennis, gnibbler, and me?

@quartata No, Dennis is family and isn't annoying.

quartata

@AlexA. the joke

quartata

your head

Dennis the Menace (U.S. comics)

Dennis the Menace is a daily syndicated newspaper comic strip originally created, written, and illustrated by Hank Ketcham. It debuted on March 12, 1951, in 16 newspapers and was originally distributed by Post-Hall Syndicate. It is now written and drawn by Ketcham's former assistants, Marcus Hamilton and Ron Ferdinand, and distributed to at least 1,000 newspapers in 48 countries and in 19 languages by King Features Syndicate. The comic strip usually runs for a single panel on weekdays and a full strip on Sundays. The comic strip became so successful that it was adapted to other popular medi...

TimmyD

VoteToClose

xD

Alex A.

9:58 PM

VoteToClose

The gif that killed chat.

Alex A.

VoteToClose

^ Me, on dates. Because I don't go to any. :c

SuperJedi224

Hello.

quartata

Mini-challenge: given a number n as input, print the first n Catalan numbers.

Alex A.

10:09 PM

n->for i=1:n println("Catalan number $i")end

quartata

@AlexA. ..

Hell, doesn't Julia have a builtin for Catalan numbers?

Alex A.

I think so

quartata

You could have at least been predictable

Anyways, I'm thinking of making that a catalog actually.

It would fit well with Fibonacci.

VoteToClose

:o

Alex A.

@quartata fit well

VoteToClose

10:10 PM

(runs to make Catalan number builtin)

quartata

@AlexA. >:(

Alex A.

Julia has catalan, which is Catalan's constant, but no Catalan number sequence generator or whatevs

Doorknob

sub c{say"Catalan number $_"foreach(1..$_[0])}

does that work? :/

quartata

@AlexA. Ooh nice.

Doorknob

Oh hey it does work!

quartata

10:12 PM

@Doorknob It does.

Doorknob

yay perl :P

quartata

\o/

Alex A.

>:O

Doorknob

oh I could golf that by replacing foreach with for because they're synonyms, right?

quartata

@Doorknob It would be shorter if you didn't make it a function and used -n instead tho

Alex A.

10:12 PM

Yes

Doorknob

oh right

Adriandmen

In Pyth VQ/.!*2N*.!+N1.!N

quartata

@Doorknob Yes

I would recommend using foreach for readability in production code though.

Just one of those things.

Doorknob

But this is PPCG :P

Alex A.

No, this is Patrick

quartata

10:17 PM

@AlexA. THIS IS PATRICK

Alex A.

I'm not a Krusty Krab.

quintopia

Sure look like one

quartata

...is anyone going to actually attempt my catalan number challenge or is Pyth going to be a lonely 1st place

Alex A.

Full program or function okay?

Julia, full program, 72 bytes: n=parse(readline());for i=0:n k=big(i);println(binomial(2k,k)÷(k+1))end

xnor

looking at it with Python, but that won't win of course

quartata

10:22 PM

@AlexA. Function's fine

Alex A.

If you're going to do an actual catalog I recommend a full program though

Doorknob

why?

Alex A.

Seems to be The Thing to Do™

trichoplax

How do we feel about insisting on full program only for a non-catalogue question?

Alex A.

Up to the OP

VoteToClose

10:23 PM

@trichoplax No.

trichoplax

Is it frowned upon? Does it exclude anyone?

Doorknob

it's annoying

Alex A.

Calvin's done it

Yeah it's annoying

trichoplax

It seems like it is restrictive without reason in most cases (I don't object where it's relevant to the challenge)

xnor

def f(n):c=1;j=3;exec("print(c);c*=4-6/j;j+=1;"*n)

Python 3

trichoplax

10:24 PM

Is there precedent off site for only accepting full programs for catalogues?

Alex A.

@trichoplax Our defaults specify that full programs or functions are fine and often when a new user insists on one or the other, they're told about our defaults

trichoplax

Yes new users usually seem fine with functions once it's pointed out

Alex A.

@trichoplax Idk. What does Rosetta Code do? IIRC Martin's idea behind catalogs was to make us the Rosetta Code for golfy solutions.

trichoplax

Good point

quartata

@xnor That's a neat trick with the exec

xnor

10:27 PM

too bad it's Python 3 so it needs parens

but Python 2 will int-divide

actually, I could just do j=3.

i'm printing floats, which i hope is OK

quartata

@xnor That's fine.

Doorknob

If only there were a Python 2.5 to keep the golfiest features from each version. :P

xnor

i probably should recurse instead

quartata

@Doorknob "Python 2.5" is too much of a mouthful though. Let's call it "Pyth" instead.

VoteToClose

Is it bad that I have 5 different versions of Python on my computer solely for testing code golf submissions?

3

Alex A.

10:28 PM

Yes

VoteToClose

Wow.

quartata

@VoteToClose No, I had 6 before I even arrived at PPCG

SuperJedi224

I have got 2.

quartata

2.4 2.5 2.6 2.7 3.2 3.4

dammit python

SuperJedi224

I only have 2.7 and 3.4

VoteToClose

10:29 PM

Can you guess what my favorite bash builtin is? c:

quartata

@VoteToClose which

VoteToClose

compgen -c

quartata

Which isn't a builtin actually, but is often mistaken for one.

VoteToClose

I would die without it. XD

quartata

@VoteToClose Oh, forgot that was a thing.

Doorknob

10:31 PM

llama@llama:~$ man compgen
No manual entry for compgen

whuzzat

2

xnor

python 2: c=1;j=3.;exec"print c;c*=4-6/j;j+=1;"*input()

VoteToClose

I don't have a Manuel page for it either. Just do compgen -c, you'll figure it out.

Doorknob

llama@llama:~$ compgen
zsh: command not found: compgen

VoteToClose

Oh.

Well then.

Doorknob

Apparently it's a Bash thing? Because it works on bash, but not zsh

VoteToClose

10:33 PM

6

A: Understand `compgen` builtin command

Options for compgen command are the same as complete, except -p and -r. From compgen man page: compgen compgen [option] [word] Generate possible completion matches for word according to the options, which may be any option accepted by the complete builtin with the exception of -p and -r, a...

Alex A.

@Doorknob This is why no one uses zsh. :P

mbomb007

[tag:logic] Logic questions are characterized by their rationality and pointy ears.
- glad this is being changed, lol

VoteToClose

You're welcome. XD

mbomb007

I voted to approve

VoteToClose

\o/

mbomb007

10:34 PM

idk why the Doctor put that

Doorknob

/me approves

mbomb007

/me me

VoteToClose

I feel like tag edits should be more than 2 rep. You'd think people would go over with a fine-tooth comb with that stuff.

Dennis

Well, it depends. If you fix a handful of typos, +2 sounds about right. If you create the thing from scratch...

VoteToClose

Eh.

trichoplax

10:38 PM

I had a look at Rosetta Code and it does seem to have full programs, although I couldn't find a rule for that. I also learned that C++ should really have been named ++C...

Cᴏɴᴏʀ O'Bʀɪᴇɴ

@trichoplax --C++

Or C+- if you're fickle.

trichoplax

Now I have to go and learn enough C to get that joke...

Cᴏɴᴏʀ O'Bʀɪᴇɴ

I don't know any C.

VoteToClose

I don't know any sea.

trichoplax

Does --C++ return C - 1 and leave C at the same value as it had beforehand?

Cᴏɴᴏʀ O'Bʀɪᴇɴ

10:43 PM

@trichoplax It's a syntax error AFAIK

Doorknob

no, it's a nonsense expression that's invalid syntax :P

trichoplax

Ah OK :)

Alex A.

There's a really interesting easter egg in C++14 though: If you type trichoplax with nothing else in the file, you get all sorts of errors.

3

El'endia Starman

@flawr I dunno, maybe something like "given a non-convex polygon, partition it into convex areas".

trichoplax

@AlexA. Um, I don't think that's new for 14 :P

Alex A.

10:46 PM

No, I heard they added that functionality. Should work fine in C++98.

mbomb007

@VoteToClose VoteToClose.next = new Date();

VoteToClose

@mbomb007 \o/

El'endia Starman

@quartata Fastest code would be interesting if we had large, complex examples. So, code golf will likely be more interesting, ultimately, and fastest code is harder to score anyway.

trichoplax

@AlexA. Now I'm hesitant, which makes me feel gullible...

VoteToClose

@mbomb007 Side note: I was totally joking. XD preserves face

mbomb007

10:47 PM

lol

Doorknob

llama@llama:~/code/misc$ cat > tricho.cpp
trichoplax
llama@llama:~/code/misc$ g++ tricho.cpp -std=c++98
tricho.cpp:1:1: error: ‘trichoplax’ does not name a type
 trichoplax
 ^

Alex A.

@trichoplax Well, it should at least yield the desired behavior in C++98.

@Doorknob This is the expected behavior in 98.

mbomb007

I wonder what color trichoplax is in CSS?

VoteToClose

How has the ><> online interpreter not been at least linked on this question?

trichoplax

So 14 introduces a slew of new errors?

Doorknob

10:49 PM

/me looks for a C++14 compiler that I may or may not actually have

Neither my clang++ nor my g++ has it :P

Alex A.

Does have C++17?

Doorknob

llama@llama:~$ g++ -std=
Completing standard
c++03    c++11    c89      c++98    gnu++03  gnu++11  gnu89    gnu++98
c11      c++1y    c90      c99      gnu11    gnu++1y  gnu90    gnu99

What's 1y?

Alex A.

One year

trichoplax

Is it like 0x?

Doorknob

oh apparently that's C++14

ok then

Alex A.

10:51 PM

1*y = 14 when y = 14

Doorknob

same error :P

El'endia Starman

alex-is-wrong

Alex A.

I said you get errors.

You have not been misled.

trichoplax

I have nothing to say in this comment

El'endia Starman

8 mins ago, by Alex A.

There's a really interesting easter egg in C++14 though: If you type trichoplax with nothing else in the file, you get all sorts of errors.

Alex A.

10:53 PM

¯\_(ツ)_/¯

El'endia Starman

"all sorts of errors" != one error.

Alex A.

That's not true

trichoplax

Indeed. There exists more than one sort of error.

Doorknob

ok Perl's wantarray is also magical

Anonymous

Length 11 snippet has been added to the showcase popcon for Seriously - this one isn't much of a secret, since I showed it off yesterday

Alex A.

10:55 PM

@Doorknob Do not want

Anonymous

@Doorknob Dark magic

Doorknob

@AlexA. backstroke of the west

Alex A.

@Doorknob wut

My backstroke is not fast

Anonymous

Perl is the Avada Kedavra of programming languages

Alex A.

My breaststroke is faster

Doorknob

10:56 PM

ok come on you can't just reference backstroke of the west and not know what backstroke of the west is :P

winterson.com/2005/06/episode-iii-backstroke-of-west.html

Alex A.

I can and I did

Doorknob

go read that ^^ :P

Anonymous

wee woo fun police here no more memes unless you know the source

Alex A.

...

xnor

@quartata Haskell f n=scanl(*)1[4-6/i|i<-[2..n]]

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