The Nineteenth Byte

aditsu

12:00

I can't think of any context in which you xor 2 chars and want the result to be a char

Ilmari Karonen

@aditsu IMO, having char (&/|/^) char -> char would be more consistent, and make more intuitive sense. I can see why char - char yields an int, because the result can be negative, but there's no such issue for bitwise ops.

XOR cipher

In cryptography, the simple XOR cipher is a type of additive cipher, an encryption algorithm that operates according to the principles: A ⊕ {\displaystyle \oplus } 0 = A, A ⊕ {\displaystyle \oplus } A = 0, (A ⊕ {\displaystyle \oplus } B) ⊕ {\displaystyle \oplus } C = A ⊕ {\displaystyle \oplus } (B ⊕ {\displaystyle \oplus } C), (B ...

Erik the Outgolfer

And you can think of one in which you want the result to be an int?

aditsu

@IlmariKaronen the key is usually an int

Erik the Outgolfer

I don't think that was what Ilmari was talking about...

I think it was about char ^ char -> int instead of char ^ char -> char.

aditsu

@EriktheOutgolfer I know

Erik the Outgolfer

12:04

Nevertheless, I can't think of any case where you would actually need char ^ char -> int.

aditsu

I'm struggling to think of a case where I want to do char ^ char :)

Erik the Outgolfer

Why special-case stuff you'll probably never need?

aditsu

how is it special case?

Erik the Outgolfer

Does it happen with all ops treating chars as ints?

aditsu

there aren't many of those

it happens with -

Erik the Outgolfer

12:08

It happens with - and ^, and & and | choke.

What was the intention with - and ^ doing (char char) -> (int)?

aditsu

with - it's very natural: converting chars to numbers

e.g. "ABC" -> [0 1 2]

subtract 'A from each

you can do something similar with ^, but you don't usually need that..

Erik the Outgolfer

But how does it make sense with ^? Consistency?

Also, & and | should support chars, because code-golf.

(Even though it's usually Jelly which is too much golfier)

aditsu

consistency, and I think it makes more sense than getting a char

Ilmari Karonen

We may need to agree to disagree on it making more sense that way. :)

aditsu

if A^B=C, I expect C^B=A

and C^A=B

Erik the Outgolfer

12:14

if char^char=int, I expect int^char=char

and int^char=char

if char^char=char, I expect char^char=char

and char^char=char

aditsu

well, I was talking about char A and int B

or vice-versa

Ilmari Karonen

@aditsu ...how would making char ^ char -> char break that? Chars are 16-bit unsigned values, they're closed under bitwise ops.

Erik the Outgolfer

@IlmariKaronen I think he means that if char1^int=char2, then char2^int=char1, and char2^char1=int. Makes some sense...

aditsu

@IlmariKaronen well, you would have 1'a^'a^ = 1c instead of 1

Erik the Outgolfer

you were ninja'd by the way

aditsu

12:18

slightly different explanation, may help

Erik the Outgolfer

btw 1c is '1 as a literal

Ilmari Karonen

@aditsu OK, that kinda makes sense, although I'm not convinced that making the type of the output obey the same algebraic laws as the bits themselves is really desirable in general.

aditsu

@EriktheOutgolfer it's not

Erik the Outgolfer

ok unprintables dont show up in chat

Ilmari Karonen

IMO, if we were designing this from the ground up, it'd make the most sense to have the result of all bitwise ops have the same type as the inputs if both are the same, and the wider type if they're different (so as not to cut off any bits of the result).

Erik the Outgolfer

12:23

Well, if you know Java you can make your own CJam derivative, it's free as in free speech code anyways. ;)

Ilmari Karonen

That'd mean char &/|/^ char -> char, int &/|/^ int -> int, and int &/|/^ char -> int.

Although, admittedly, having int &/|/^ char -> int would mean that you couldn't do, say, string f^ int -> string, which I guess is a valid counterargument. :/

Anyway, all I'm really saying is that char & char and char | char should produce something.

Erik the Outgolfer

Basically, aditsu's perspective is that if we have three literals A, B, and C such as A ^ B = C, then you would expect that C ^ B = A and C ^ A = B, and the last two expression would return A and B exactly, including their type, i.e. true equality.

@IlmariKaronen That's a good suggestion btw.

Ilmari Karonen

@EriktheOutgolfer Actually, char & char -> char and char | char -> char would even be consistent in that sense (since, algebraically, (A & A) = (A | A) = A).

Erik the Outgolfer

Since A =/= A would always be false, this is true.

@IlmariKaronen char & int -> int then right?

or char | int -> int, int & char -> int, int | char -> int

betseg

I have a challenge idea but I don't know what to title it

Erik the Outgolfer

12:31

What is it?

betseg

xkcd.com/1179 write today's date formatted as the date on bottom left of the cat

Adám

@betseg I think we have that already.

Erik the Outgolfer

@betseg I think it's a dupe.

betseg

Oh I couldn't find it

Ah I found it

Ilmari Karonen

@EriktheOutgolfer If we took the whole "types follow the same rules as the bits" idea all the way, and basically assumed that integer-ish variables have a hidden "is a char" bit that obeys the same algebraic rules, then we'd have char | char -> char, char & char -> char, char ^ char -> int, int | char -> char, int & char -> int and int ^ char -> int.

And, of course, int | int -> int, int & int -> int and int ^ int -> int.

But I think that would probably be a silly thing to do in practice.

Erik the Outgolfer

12:38

You complicated it beyond human comprehension.

Jan Dvorak

@IlmariKaronen disagreed. It seems like the best option to me.

Ilmari Karonen

@JanDvorak Really? Even the "int | char -> char, int & char -> int" part? :p

Erik the Outgolfer

Did you think of that part randomly?

Jan Dvorak

@IlmariKaronen Why not?

char & 1 = char % 2 = 0 or 1

similarly, char | 1 lets the lowest bit of the char code but you still want to keep it a char

Ilmari Karonen

@EriktheOutgolfer No, it follows perfectly logically from the assumption that "is a char" is a boolean property that obeys the same rules as the actual data bits. :)

Erik the Outgolfer

12:43

Oh, but what if we had "is an int" instead? I know, would make less sense for a golfing language.

@IlmariKaronen You got me.

Jan Dvorak

@EriktheOutgolfer then int ^ int = char

which would be pretty bad

Erik the Outgolfer

Yeah, "is a char" makes more sense.

Jan Dvorak

Bitwise negation shouldn't touch that bit, though

Erik the Outgolfer

@JanDvorak Because it would automatically mod by 65536, right?

Like, bit width would be cut.

Jan Dvorak

because 0 xor 0 is 0, not "\0"

Ilmari Karonen

12:45

@JanDvorak :DDD

Jan Dvorak

now, "\0" xor "\0" being 0 is perfectly fine

Erik the Outgolfer

Well, in code golf, and generally general programming, you would be dealing with ints more than with chars.

Mayube

> generally general programming

Erik the Outgolfer

Yeah, I thought about changing it to something else.

Jan Dvorak

After all, characters are just integers with the char bit set.

Ilmari Karonen

12:49

...and all bits above the 16th cut off.

Jan Dvorak

24th

Ilmari Karonen

You're thinking of Unicode... in CJam it's 16.

Erik the Outgolfer

no its 16th

Jan Dvorak

20th, m'kay? I'm not going lower.

Erik the Outgolfer

@JanDvorak We're now talking about using chars as ints, and expecting high numbers???

CJam only supports 16 bits.

Jan Dvorak

12:52

Don't have your hands tied by the early installment weirdnesses of your precedents.

Native emoji support is a great selling point

Erik the Outgolfer

true

Try it online!

Where the upper bound can be useful...

Jan Dvorak

"😀" ^ "😐" ^ "😠" == "😰"

"🙈"^"🙉"^"🙊"="🙋"

TuxCopter

Haha, that's awesome

Ilmari Karonen

13:09

@aditsu Anyway, I'm pretty sure there's no way to assign return types to CJam's bitwise ^ so that A B A ^^ would always have both the same value and the same type as B. So any attempt at "algebraic consistency" is doomed to fail somehow in any case.

Under the current rules, for example, setting A to a char and B to an int makes ABA^^ equal to Bci, or B65535&.

mbomb007

13:39

My rep is a palindrome :)

Jan Dvorak

@IlmariKaronen easy: use the type bit. Then ^x is always bipotent.

int xor char = char, char xor char = int

Ilmari Karonen

@JanDvorak The problem is that CJam's ints are bignums, while chars only have 16 bits. So int -> char is necessarily a lossy operation.

Jan Dvorak

Support arbitrary precision characters then :-D

Ilmari Karonen

That would work, but it'd be a more fundamental change to the language. (Also, it'd break at least one established golfing trick. :P)

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

The circumference of an ASCII art object. code-golf ascii-art geometry Challenge: Create a function that takes in piece of ASCII art as a string and returns an int that is the length of the outer edge of the ASCII art in characters. Test Cases: input: * *** ******* *** ...

Phoenix

14:00

> Strictly speaking, the GNU C preprocessor does not support all programs in ANSI Standard C unless `-trigraphs' is used, but if you ever notice the difference it will be with relief.
You don't want to know any more about trigraphs.

gcc.gnu.org/onlinedocs/gcc-2.95.3/cpp_1.html#SEC42

Mayube

@Phoenix so what you're saying is we need to make trif**k?

Phoenix

Is that an esolang you're proposing? Probably.

Mayube

well there are 9 characters in trigraphs: #\^[]|{}~

brainf**k has 8 characters in it's language

so we do brainf**k, but using #^[]{}|~ instead of the usual characters, but then have the actual language written in trigraphs for those characters

Phoenix

Go ahead

Mayube

Wait so J is based on APL, and Jelly is based on J... this explains a lot

Leaky Nun

14:13

@Mayube what does this explain a lot?

Luis Mendo

The function trains, probably

Leaky Nun

CMC: determine if an integer is square-free

Mayube

square-free?

Leaky Nun

14:28

is not divisible by any perfect square except 1

Mayube

ah ok

Luis Mendo

@LeakyNun Output true/false or truthy/falsey?

Leaky Nun

@LuisMendo the latter

Luis Mendo

YfdA

Prime factors, consecutive differences, all

Leaky Nun

I see

Phoenix

14:32

Mathematica, 29 bytes: Solve[Mod[#,x^2]==0,x,Integers]&. {} is true, all other output is false.

Wheat Wizard

Hey my challenge here was closed as a duplicate but I really don't think it is. The biggest difference is my challenge requires two functions making is significantly harder. In addition my challenge has significantly different rules on how they should be different, with laxer requirements. Could people take a look?

Phoenix

If you want to be pedantic about true/false, add =={} for +4 bytes

Leaky Nun

@Phoenix is there no golfier way?

Phoenix

Probably, but I'm lazy.

New Main Posts

0

Q: Try to make a square!

the challenge is that with a given input the program should make a 3x3 square representation of that input for example: input: # output: ### # # ### Inputs are allowed but you are also allowed to use flags. okay? start coding!

code-golf

0

Q: Perform gravity sort

Challenge Given a list of integers, show how gravity sort would be done. Gravity Sort In gravity sort, imagine the numbers as rows of asterisks. Then, everything falls, and the new rows will be obviously sorted. Let's look at an example: [2, 7, 4, 6]: ** ******* **** ****** ------- ** **** *...

code-golf ascii-art sorting

Leaky Nun

14:35

omg I missed those questions

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Sigmafy the expression code-golfmatharithmeticnumber For those who didn't know, Sigma is a Greek letter which is heavily used in mathematics as the summation sign. Given a string representing an expression depending on k that we will denote E(k), print the sum of the results for E(k), with each...

Mayube

15:07

I'm here too

Erik the Outgolfer

@Christopher FYI That's considered noise.

> Sometimes, there isn't anybody talking in chat. That's perfectly fine. Don't send messages just because the room is quiet.

Christopher

@EriktheOutgolfer Fool proof way to summon users.

I get it though. I was just being lonely :P

2

A: Turing complete language interpreter code golf

x86 assembly (Intel syntax/MASM)-Brainfuck 2547 bytes. Being honest here this can be golfed a good amount. I have golfed a large amount of bytes off but variable can still be golfed. However trying to golf the different names is a pain but would save only a small amount of bytes. This won't win...

How do I count the bytes?

Erik the Outgolfer

@Christopher Why summon them if you don't need them? Also, if you have a question directed at the whole TNB, just ask the question, they will be summoned if they are interested in answering it. ;)

Christopher

24 hours ago, by Christopher

@Riker True TNB is my life

Erik the Outgolfer

Also, that's why Riker said it's sad that TNB is your life.

ninja'd

Christopher

15:10

@EriktheOutgolfer :P I have an hour at school that I have nothing to do so i TNB

Mayube

@Christopher I'm just guessing here but I think you compile it then hexdump?

Christopher

@Mayube i can't compile it rn

:(

Nathan Merrill

you'll want an assembler

Phoenix

You could use TIO

Christopher

@Phoenix TIO is linux the code is intel

Phoenix

15:20

Linux is an OS, no matter how you are using the term intel it isn't that.

So I'm not sure what you mean.

Christopher

Intel syntax/MASM

Tio appears to not be that. Also imports and such don't work on tio

TIO is not MASM

Mayube

TIO only supports ac, gcc and nasm

New Meta Posts

0

Q: How are bytes counted in assembly?

I was told bytes in assembly are counted by the byte of machine code. Is that true? If so what steps should be taken to correctly get bytes?

discussion code-golf faq-proposed

Phoenix

MASM can be compiled under Linux using JWasm

I've put in a request for it to be added to TIO.

Ayoungcoder

can someone tell me why my challenge: codegolf.stackexchange.com/questions/120052/… is put on hold? there are a lot of people that understand the questions and i dont see any problem with it?

if there is a moderator in here, please deflag it

Leaky Nun

15:28

It is bad practice to ask for moderators to hammer it.

2

Ayoungcoder

okay didnt know

sorry mods

ill just wait for them to look at my report

Leaky Nun

but there are already 4 reopen votes

one more vote to reopen

Erik the Outgolfer

I don't think he can see the reopen votes.

Ayoungcoder

no i cant

Leaky Nun

@EriktheOutgolfer which is why I'm telling him/her

Ayoungcoder

15:29

but still thanks

Nick Clifford

CMC: given a pair of rectangular coordinates (x, y), find a matching pair of polar coordinates (r, θ) where θ is in degrees.

Ayoungcoder

lets try to get it guys :)

Christopher

Done. Opened. Irony as I closed it as the final vote and opened it as the final vote.

Ayoungcoder

thanks

Phoenix

Question is still poorly written IMO. Shouldn't be closed tho

Ayoungcoder

15:30

phoenix what would you suggest to add

Christopher

@Ayoungcoder try to sandbox posts first however. codegolf.meta.stackexchange.com/questions/2140/…

Luis Mendo

> Capitalization man, Is your shift key broken? :P

@WheatWizard :-)

Christopher

@Ayoungcoder Grammer

Ayoungcoder

lol ill look into that

Christopher

@Ayoungcoder Also don't accept an answer for a week or so.

Ayoungcoder

15:31

okay im new here so i dont know all the dos and donts

Wheat Wizard

(or ever)

I have the Opposite problem with capitalization where I over capitalize everything

Christopher

@WheatWizard Sheesh. I accept for that +2 rep :) I think that is why Dennis does also.

Ayoungcoder

i can't find any grammar or capitalization errors, can someone show me that

Wheat Wizard

I'm not a fan of accepts, but each their own

Leaky Nun

@Christopher what is wrong with the grammar?

Wheat Wizard

15:33

@Ayoungcoder I fixed them in an edit. I think its good now

Christopher

@WheatWizard I have the problem of caps on the first two chars. OKay

@WheatWizard Accepts on KoTH are good

Erik the Outgolfer

Generally accepts are good. Hence the +2.

Ayoungcoder

thanks guys

Erik the Outgolfer

That is, except if the challenge is a catalog.

Wheat Wizard

I'll take your word for it. I don't like KoTHs either :P

Phoenix

15:34

Just looked at my first challenge. Kind of amazed I got a score of 24 on it.

Leaky Nun

@Ayoungcoder you may want to refer to here

Christopher

@Phoenix Sheesh

Leaky Nun

@Ayoungcoder Also, do you mind if I edit your question?

Christopher

@LeakyNun Edit at will :P

Leaky Nun

@Christopher I'm not asking you

Phoenix

15:34

@Christopher My second challenge got around -10 :P

Ayoungcoder

leaky i would be happy if you did :)

Christopher

@LeakyNun opps thought you were a <1k rep XD

Wheat Wizard

I don't like accepts because they pin the answer to the top. Often the shortest answer is not the best. In addition the accepted answer is only controlled by the OP, so if they become inactive it can't be changed

Erik the Outgolfer

code-golf = the shortest answer is the one which should be accepted

Leaky Nun

@Ayoungcoder I can't edit if you keep editing

Wheat Wizard

15:36

The sort by votes is already Broken as fuck, so I don't think we need pinned answers.

Ayoungcoder

sorry leaky :)

ill just keep the current accepted as accepted and edit it if a lower one comes by

Luis Mendo

Funny how this challenge has 14 votes and a total score of 0

Erik the Outgolfer

@WheatWizard That's why I never use sort by votes.

Ayoungcoder

people hate me

depression lol

Erik the Outgolfer

We don't hate you, we prepare you. ;)

Luis Mendo

15:37

You'll learn. At the beginning, it's hard to write a properly specified challenge :-)

Christopher

@Ayoungcoder Nah. It was probably just geobits :P

Phoenix

People don't hate you, people are just incredibly critical of the content quality.

Christopher

@Phoenix first was +11 codegolf.stackexchange.com/questions/102618/…

Ayoungcoder

i dont like the peopole who downvote questions but dont say why they did, but thanks to you guys

trichoplax

Relevant:

24

A: We're not a Q&A site. But what should be done about it?

Remove the Accept feature This feature is likely way too integral to how SE instances work for this to be possible without forking the software, but I don't think the concept of accepted answers is useful on PPCG. The most fundamental pillar of this community is that every single question needs...

Kritixi Lithos

15:38

@Phoenix Nobody "hat"s anybody

2

Phoenix

Edit ninja'd

Christopher

@Ayoungcoder I downvote people and sometimes don't say why as it is clear

Ayoungcoder

my 7 downvotes weren't clear but i guess it was for those people

Christopher

-2

Q: Calculate my reading speed

You must create a program that calculates my reading speed! The challenge First when the program is run wait for user input (a click or a keyboard key being hit you may choose one. When the user "triggers" the program print the paragraphs imported. Then when the user hits another key/click end ...

code-golf kolmogorov-complexity

Ayoungcoder

again thanks to you guys for helping

trichoplax

15:39

Downvoting and explaining why are two separate tasks. Downvoting is anonymous so the same person doesn't have to do both, which makes it more likely we'll have downvotes, which makes it more likely we'll have explanations eventually.

Ayoungcoder

i don't get that idea but whatever, i guess its a stackexchange thing

lol and i went up 32 rep from this question, that made my day! :)

Arjun

BTW, I am going to post a challenge tomorrow (It's 9:10 pm here in India right now)! Which phase of the day is most suitable for posting challenge (so that most number of people view it)?

trichoplax

Otherwise people would hold back with downvoting, which would be bad. We need downvotes to identify when things need changing

Ayoungcoder

@Arjun i'd try to put it in at around 7 o clock in the evening for america

Erik the Outgolfer

Yeah, that's probably the best time.

Leaky Nun

15:42

@Ayoungcoder there are downvotes. Get over them.

trichoplax

Is it the kind of challenge that will appeal to people in the office or when they get home?

Ayoungcoder

@LeakyNun who that was a big reformat of my question, thanks

Luis Mendo

"In the office" highly depends on the part of the world you live in

Arjun

I guess most of the people on PPCG are from America, aren't they?

trichoplax

Indeed, but it seemed like a good start before narrowing down when the most office work would be happening (or the most being at home, accordingly)

Business Cat

15:43

There's a lot from Europe too

Erik the Outgolfer

Office work seems more appropriate.

Leaky Nun

@Ayoungcoder My highest-voted challenge also has the most downvotes.

Phoenix

Aug 7 '15 at 18:38, by aditsu

abandon all work, ye who enter here

Wheat Wizard

Could we please get banned from the HNQ

trichoplax

That would leave the HNQ half empty...

9

Erik the Outgolfer

15:45

@trichoplax Are you sure? The space will be covered.

Also, being exempt from HNQ isn't a thing I think.

trichoplax

@EriktheOutgolfer Yes you're right of course - I was just joking because there are so many PPCG questions there recently

Adám

What is HNQ?

Erik the Outgolfer

@trichoplax Yeah I understood the joke.

@Adám hot network questions

trichoplax

MO has no HNQ sidebar, but still appears on other site's HNQ

Luis Mendo

MO has no HNQ sidebar MO are serious people :-P

trichoplax

15:46

@Adám The productivity killer on the right hand side of SE pages

10

Adám

@trichoplax MO?

Luis Mendo

Math Overflow

trichoplax

[mo]

Phoenix

MathOverflow

Ninja'd

trichoplax

OK that doesn't work...

Erik the Outgolfer

15:47

@trichoplax ninja'd

Phoenix

Luis Mendo

It's the "reasearch-level" counterpart of Math.SE

Erik the Outgolfer

You type mathoverflow.com.

Luis Mendo

Nope

Leaky Nun

@Phoenix thanks for the inspiration for the title of my to-be-posted challenge

trichoplax

15:49

Maybe because it's its own domain separate from SE

Phoenix

mathoverflow.net

Luis Mendo

@LeakyNun If you want it to sound catchy, that phrase is, but it's also well known and perhaps a little stale by now

Leaky Nun

@LuisMendo I won't use that phrase directly.

Arjun

I will be posting my challenge 32-33 hours from now. Will that be okay?

Christopher

Try to select it for you non meme browsers

Luis Mendo

15:52

"work"?

Phoenix

Try selecting the text

Erik the Outgolfer

Sandbox

Where you can play with chat features (except flagging) and ch...

2

trichoplax

"Does that still work" is a question to ask in the sandbox

Leaky Nun

@Arjun post your challenge whensoever you want.

Luis Mendo

Hah. Cool!

Erik the Outgolfer

15:53

@trichoplax ninja'd

trichoplax

I'm not doing well today...

Christopher

@trichoplax I fixed it

trichoplax

I meant the thing you're trying too...

Erik the Outgolfer

Guys, the sandbox exists!

4

trichoplax

One warning is enough. Kicks from now on

John Hathwood

15:54

Hello friends!

Arjun

Hi!

Phoenix

\o

Christopher

I don't understand what happened

trichoplax

@Christopher What are you looking to understand?

user165474

Wait who's being kek'd?

Christopher

15:56

^ that

trichoplax

As long as everyone who needs to uses the sandbox, no one.

If you're not sure what something will do, find out in the sandbox first. Nothing more complicated than that

Arjun

@trichoplax What does Pro Tempore mean?

Phoenix

Provisional Temporary

trichoplax

translate: pro tempore

Hmm. I seem to have lost my translate powers

Phoenix

It's Latin for "For the time being"

(Wikipedia)

trichoplax

15:59

In the context of SE mods, it means the moderator of a Beta site, as opposed to an elected moderator of a graduated site

Sandbox

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