The Nineteenth Byte

Mr. Xcoder

11:00

@EriktheOutgolfer Can we return the numbers separated by a newline instead of formatting them as a list

Erik the Outgolfer

yeah that's a reasonable format

Mr. Xcoder

Noo, I've been ninja'd by Rod :((

Erik the Outgolfer

heh mine is even shorter but let's say I won't post it...

Mr. Xcoder

@EriktheOutgolfer Does yours use [A::B] syntax?

Erik the Outgolfer

let me rewrite it one moment

@Mr.Xcoder nope

btw mine is 52 bytes

Mr. Xcoder

11:07

I think I have something even shorter

Not done yet

Erik the Outgolfer

@Mr.Xcoder well if it works then post it...

Mr. Xcoder

> Not done yet

Erik the Outgolfer

yeah...but python may surprise you on that

that is, I often think I can outgolf somebody and think of a clever method and then oops it came out too long without me realizing it

Mr. Xcoder

Hopefully Python's still today :)

A 59 one has appeared

ASCII-only

Which challenge

Mr. Xcoder

11:12

The new one

ASCII-only

Also what are the three most important (?) list methods? map, reduce and all right?

Mr. Xcoder

reduce is from functools, so i'd say no

all,any,map and zip

Because you have to import functools

Erik the Outgolfer

nvm I thought you were talking about something else

btw you don't have to import functools in python 2 ;)

Mr. Xcoder

@EriktheOutgolfer 49 bytes

Erik the Outgolfer

if it works post it

Mr. Xcoder

11:19

I now think I mad a mistake :)

@EriktheOutgolfer Posted

ASCII-only

@Mr.Xcoder all other languages have it builtin though, it's just guido is weird

@Mr.Xcoder *46

Mr. Xcoder

@ASCII-only Thanks

Why is my answer ignored?

Erik the Outgolfer

@Mr.Xcoder and now down to 41

Mr. Xcoder

@EriktheOutgolfer You golfed it down to 41?!

Erik the Outgolfer

it's a bit different than the python answers already in

Mr. Xcoder

11:23

Including mine?

Erik the Outgolfer

@Mr.Xcoder yeah printing newline-separated

@Mr.Xcoder yes

ASCII-only

42 bytes

Mr. Xcoder

@ASCII-only May I borrow that?

<joke>

Erik the Outgolfer

heh rod did it in 36

Mr. Xcoder

Dang

Erik the Outgolfer

11:31

but that's python 3

ASCII-only

@EriktheOutgolfer it's a polyglot

totallyhuman

ohh boy here comes an excel answer o0

Mr. Xcoder

@EriktheOutgolfer Not much of a difference

Erik the Outgolfer

@ASCII-only ikr

ASCII-only

CMC: Do it in Charcoal :P the shortest way will probably be repeated calls to input

Mr. Xcoder

11:36

I got mine down to 41 :)

Erik the Outgolfer

@Mr.Xcoder full program right?

Mr. Xcoder

@EriktheOutgolfer Yep

Erik the Outgolfer

oh my...that's byte-by-byte my approach

Mr. Xcoder

@EriktheOutgolfer This one:

l=input()
while l:print l[0];l=l[l[0]+1:]

Erik the Outgolfer

even the l is the same

Mr. Xcoder

11:37

@EriktheOutgolfer I read minds :-)

Erik the Outgolfer

@Mr.Xcoder yep

ASCII-only

Hmm any idea for operator chars for all/any/zip in charcoal?

Or overloads where they'd make sense

totallyhuman

zip is of course a zip

there's gotta be a character that looks like a zip

Erik the Outgolfer

@ASCII-only not overloads

Anonymous

The pains of trying to use PPCG to practice a new language: 1) See a new, interesting challenge. 2) Write a solution to said challenge, after spending 15 minutes looking up stuff. 3) Look at challenge again, and see an answer in that language posted 14 minutes ago that drastically outgolfs your solution.

Anonymous

11:41

@totallyhuman ¥ kinda does

Erik the Outgolfer

@Mego you mean 14 hours ago?

Anonymous

@EriktheOutgolfer I don't know how someone would post an answer before the challenge is written.

Erik the Outgolfer

well, for me new challenges are posted some >10 hours ago

because I need sleep too

totallyhuman

oh great somebody upvoted my brainfuck answer to 49 votes

just... there at 49

Anonymous

I should do PE instead so that I don't have to see how badly I get ninja'd/outgolfed

Mr. Xcoder

11:43

@totallyhuman Believe me, you feel much worse at 89.

totallyhuman

lol

Erik the Outgolfer

@Mego what's pe?

ASCII-only

@Mego Good luck PE is like 100x more complex than PPCG

Anonymous

Project Euler

Erik the Outgolfer

you don't even need to write the program at all there just use google

unless you want to challenge yourself

Mr. Xcoder

11:45

@EriktheOutgolfer The best part of PE is to not use Google :(

Anonymous

@ASCII-only I think I'll be ok

Mr. Xcoder

WOW

Erik the Outgolfer

@Mego that's not really you is it?

Mr. Xcoder

I'm not even Level 1

Anonymous

@EriktheOutgolfer It is

Mr. Xcoder

11:47

@EriktheOutgolfer Of course it's him

ASCII-only

Anonymous

I haven't done PE in a long time (I think since the newest was in the 300s)

totallyhuman

@ASCII-only jeez

ASCII-only

@totallyhuman Well not really that surprising since he does puzzles over at Puzzling a lot and is really good at Code Jam as well

Mr. Xcoder

Oh my god @Sp3000, you're a PE god

@ASCII-only Code Jam?

Sp3000

11:52

Hm? Oh hey

Mr. Xcoder

Hi

Erik the Outgolfer

hi

totallyhuman

hasn't been here in a while though

ASCII-only

@Sp3000 Wait what do you always lurk here

Sp3000

I'm just next door most of the time, but yes I do lurk here too nowadays

Mr. Xcoder

11:54

@Sp3000 Why did you kind-of stopped posting on PPCG?

Sp3000

(next door being Puzzling)

ASCII-only

Also I forgot to try and stalk you like two weeks ago when I was on holiday (damnit I really should have)

Sp3000

A combination of full time work and too many things I've been wanting to do

(mostly the former)

Mr. Xcoder

Oh, I see. We want you back :)

totallyhuman

@totallyhuman i got ninja'd by lag

Leaky Nun

12:01

@Mr.Xcoder no, that's in the comment of the fast inverse square root

whose code I borrowed

Mr. Xcoder

Oh, ok

I was wrong :(

Leaky Nun

Fast inverse square root

Fast inverse square root, sometimes referred to as Fast InvSqrt() or by the hexadecimal constant 0x5f3759df, is an algorithm that estimates 1/√x, the reciprocal (or multiplicative inverse) of the square root of a 32-bit floating-point number x in IEEE 754 floating-point format. This operation is used in digital signal processing to normalize a vector, i.e., scale it to length 1. For example, computer graphics programs use inverse square roots to compute angles of incidence and reflection for lighting and shading. The algorithm is best known for its implementation in 1999 in the source code of Quake...

betseg

Mr. Xcoder

Could you imagine assembly winning anything?

betseg

it won this one

Anonymous

12:07

I finally got around to getting the Pi achievement on PE

LegionMammal978

12:23

Can anyone here read x64 assembly? Trying to understand some objdump -d output

Noah Cristino

hi

@LegionMammal978 me

LegionMammal978

0000000000000870 <compiledFunction1>:
 870:	48 8b 02             	mov    (%rdx),%rax
 873:	66 0f ef c0          	pxor   %xmm0,%xmm0
 877:	f2 48 0f 2a 05 d0 07 	cvtsi2sdq 0x2007d0(%rip),%xmm0        # 201050 <I0_0>
 87e:	20 00
 880:	f2 0f 58 00          	addsd  (%rax),%xmm0
 884:	31 c0                	xor    %eax,%eax
 886:	f2 0f 11 01          	movsd  %xmm0,(%rcx)
 88a:	c3                   	retq

Pretty sure it does something with floating point

iirc it's supposed to add 1 to something

Just not sure what these instructions do

Noah Cristino

what is rdx?

LegionMammal978

idk, probably set before calling

Noah Cristino

what's it set to

LegionMammal978

12:25

lemme look

Noah Cristino

kk

LegionMammal978

Hmm, couldn't find an outside reference, here's the full command and output

Maybe it's just called externally, due to it being a .so?

Noah Cristino

I'm not sure

you should decompile with something like

LegionMammal978

@NoahCristino Couldn't find anything for that costing less than $560 or something

Noah Cristino

IDA

nvm that's expensive

I got a free one

OllyDbg

you can run line by line and see how the registry changes

LegionMammal978

12:30

@NoahCristino Doesn't seem like it would work with ELF

Noah Cristino

it does

just try it

LegionMammal978

But yeah, you know what pxor, cvtsi2sdq(?), addsd, movsd do individually?

Noah Cristino

try google

LegionMammal978

...

this doesn't make much sense

Noah Cristino

one sec I'm busy

Anonymous

12:40

@LegionMammal978 cvtsi2sdq converts an int to a double

Anonymous

pxor is bitwise XOR, addsd and movsd are add and move for scalar double-precision values (fancy SIMD way of saying "do this on the float in the lowest bits and not all the floats in parallel")

Anonymous

So the assembly reads (line-by-line) as: 1) move the value pointed to by %rdx to %rax. 2) XOR %xmm0 with itself (effectively zeroing it). 3) convert the value stored at mem[%rip]+0x2007d0 from an int to a double and store it in %xmm0. 4) I have no idea? 5) Add the value pointed to by %rax to %xmm0. 6) Zero %eax. 7) Move the double from %xmm0 to the location in %rcx. 8) Return.

Anonymous

So it looks like it takes input as a double* in %rdx, stores it in %rax, adds the int value at some memory location, moves the result to a value pointed at by %rcx, and returns.

Anonymous

If that memory location has a 1 in it, then yes, it adds one to a double (using pointers).

Business Cat

I now have +7 on a Jelly FGITW answer and +1 on a PHP answer I actually put some amount of effort into. Why does voting have to be like this -_-

totallyhuman

12:56

🤷‍♂️ "omg lolz this is so short is this real codez xD +1"

Business Cat

Probably HNQ effect

THe one I answered with Jelly was 7 times as many answers

Leaky Nun

2

A: Float 754 to Hamming

C (gcc), 63 bytes f(double d){long s=0,n=*(long*)&d;for(;n;n*=2)s+=n<0;return s;} This solution is based on @LeakyNun's answer, but because he doesn't want to improve his own answer, I'm posting here more golfed version. Try it online

> This solution is based on @LeakyNun's answer, but because he doesn't want to improve his own answer, I'm posting here more golfed version.

Did anyone see that comment?

New Main Posts

1

Q: How Cloudy Is It?

Challenge Given an image of the sky, you must output the cloud cover in oktas. The image supplied will be an image file (the type is up to you) and the output should be to STDOUT. Oktas In meteorology, an okta is a unit of measurement used to describe the amount of cloud cover at any given loc...

trichoplax

@LeakyNun The PPCG mods might be able to tell you if the comment was posted and deleted for some reason.

Leaky Nun

@Dennis please help me :p

also, it's actually not that hard to do the challenge without using bithacks

Anonymous

13:05

@LeakyNun This is an English-only chatroom. Please refrain from using non-English languages.

trichoplax

@LeakyNun You can see the comments that person has posted - a quick glance at the recent ones seems to rule out them accidentally posting the comment on the wrong answer, so deletion is the only other explanation I can think of. Unless they say comment but actually mean suggested edit - which could have been rejected by others before you even saw it. (Their rep makes this a possibility)

Leaky Nun

@trichoplax thanks

Anonymous

@trichoplax The queue says it wasn't a suggested edit

Leaky Nun

@Mego so he's lying...

trichoplax

@Mego Thanks - I was just trying to work out how to find that page...

Leaky Nun

13:09

or the comment somehow didn't get sent out

Wheat Wizard

This is a thrilling mystery.

Anonymous

@LeakyNun Or the comment existed but was deleted. Only a PPCG mod would know for sure, and I don't think they'd give out that information without permission from the user.

trichoplax

@LeakyNun Perfectly plausible that a comment would have been lost along the way. Not so plausible that they saw something indicating you rejected it

Leaky Nun

@Mego right, I forgot that possibility

but as trichoplax says, he wouldn't have seen me rejecting the comment

trichoplax

Since posting a golfed version of someone else's code isn't against any rule, there doesn't seem to be anything against site policy here, just the impression of deception. I'm going to assume there's an innocuous explanation I can't think of for now.

Anonymous

13:12

They could have interpreted not implementing the suggestion in X amount of time as rejecting the suggestion.

Anonymous

I think that's probably what happened - impatience got the better of them.

Leaky Nun

@trichoplax I didn't say there's a problem with him posting a golfed version of my code

Poke

trying to learn a little hexagony

Try it online!

Leaky Nun

I'm just curious because he said that I rejected his comment, which is impossible to being with

Poke

not sure what's going on here

Leaky Nun

13:17

@Mego so you're suggesting that he deleted his own comment?

Poke

the last ^ should move to the left neighbor

because -4 is at the MP

Leaky Nun

@Poke what's the intended output?

Poke

I was trying to do a simple 3%4

so the output should be 3

Wheat Wizard

Hey I just wanted to share my meta answer, because I'm interested in discussing its contents with the community. I get the feeling it has only ben viewed a few times and I just wanted to make sure we have a full discussion.

Poke

think i'm still missing a piece of the control flow or something

Leaky Nun

13:18

@Poke you can use a backtick to debug

trichoplax

@LeakyNun Of course - I wasn't disagreeing with anything you said, just pointing out that the apparent poor behaviour isn't rule breaking

Poke

@LeakyNun that hasn't worked for me on tio

Anonymous

@LeakyNun Or it was deleted by a mod (possibly via flags)

Leaky Nun

@Poke after three ^ you should have got to a place you haven't visited

because ^ should have cycle 6

@Poke but the memory should have 3, 1, and -4 after all the parentheses...

Poke

@LeakyNun As far as I can tell there are infinite memory edges. ^ is supposed to move to the right neighbor if the current value is positive and to the left neighbor if the current value is 0 or negative

so when the current value is -4 i would expect to move back to the 1

i guess i can test if i'm thinking about this correctly with curly braces

Leaky Nun

13:22

@Poke no it wouldn't

6

1 is where you start at

right turn takes you to 2

another right turn takes you to 3

wizzwizz4

Is this Hexagony?

Poke

yes

Leaky Nun

then a left turn takes you to 4

Poke

oh...

that makes more sense

and is way more confusing in general

haha

Leaky Nun

and i should have done the picture with two hexagons

if you can see it

Poke

13:25

yeah i see what you mean

Cows quack

@LeakyNun +1 for the high quality professional graphics design

Poke

wow it's pretty tricky to get back to the edge you want

Erik the Outgolfer

@LeakyNun +1 for precious art

Poke

@MartinEnder I have renewed appreciation for anything you write in this language

Leaky Nun

@EriktheOutgolfer do the float challenge in Pyth?

Poke

13:27

so if i go to my right neighbor 6 times, i should get back to where i started?

Leaky Nun

@Poke yes

Poke

excellent

totallyhuman

You mean +★

betseg

@LeakyNun chemspider.com/Chemical-Structure.20647.html ?

Leaky Nun

@betseg lol

Martin Ender

13:33

did someone say Hexagony?

Leaky Nun

@MartinEnder please investigate the incident earlier lol

35 mins ago, by Leaky Nun

Did anyone see that comment?

wizzwizz4

@MartinEnder Yes.

10 mins ago, by Leaky Nun

totallyhuman

No, nobody can say that name without confusing themselves

Erik the Outgolfer

wait hexagony is a property of geometrical shapes or something? :p (did I spell that right?)

officialaimm

Is the name Hexagony a play on Hex-agony?

wizzwizz4

13:36

@EriktheOutgolfer I don't understand the question and yes, respectively.

Poke

@LeakyNun Just re-read the docs. I need the -d flag for backtick annotations

Martin Ender

@Poke it's easier if you use the unconditional MP-movement commands :P

totallyhuman

What is geometry?? What is a hexagon??? /s

wizzwizz4

@officialaimm Hexagon and agony, probably.

Martin Ender

@Poke I think that doesn't work on TIO though because the way I implemented the flags is stupid

Poke

13:37

@MartinEnder yeah just trying to teach myself how it all works. not sure why i started with ^

wizzwizz4

@MartinEnder Easier =/= golfier

Erik the Outgolfer

@wizzwizz4 I mean, well, I thought hexagony is the property that defines if a shape is a hexagon or something?

Martin Ender

same byte count usually

wizzwizz4

@EriktheOutgolfer That's this.n==6.

Martin Ender

@officialaimm yes

AdmBorkBork

13:44

stupid PowerShell

totallyhuman

2 days ago, by AdmBorkBork

PowerShell is great and does all things.

AdmBorkBork

They're not mutually exlucsive

totallyhuman

:P

TheLethalCoder

Finally got silver code golf :)

totallyhuman

Nice

Arjun

13:52

After such a long time, I am here....

totallyhuman

Are you really

Or is it all an illusion

Arjun

I wonder whether anyone thought I was dead. :P

But maybe I was not popular enough to be the subject of someone's concern. :P

Nor will I ever be.

Erik the Outgolfer

@LeakyNun hmm...was reading about ieee 754...couldn't cope with it

that is, well, I have stuff to do with my life

Arjun

Gtg, bye

Martin Ender

@EriktheOutgolfer I'm not sure what you mean by base encoded?

Erik the Outgolfer

14:04

@MartinEnder it seems your 8-byte alice answer is using base-10 string input (e.g. "12345" instead of [1, 2, 3, 4, 5])

Martin Ender

no it uses code points

12345 is [49, 50, 51, 52, 53]

it can represent any integers that correspond to valid unicode code points

Erik the Outgolfer

oh so it would be "\x01\x02\x03\x04\x05" or something?

Martin Ender

(so most integers up to 1114111)

@EriktheOutgolfer yes

Erik the Outgolfer

not sure if that would be valid...what is alice's natural integer upper limit?

Martin Ender

alice uses arbitrary precision integers

Erik the Outgolfer

14:07

hmm...default consensus seems to be that you have to support more than 1114111 then...

Martin Ender

fair enough. an upper bound on the input values in the challenge would make sense though (2^31-1 or something)

Erik the Outgolfer

I don't think an upper bound like 2^31-1 would be fair to all languages

also there's the no abusing datatype bounds loophole

btw 1114111 would still be too small if I put an upper bound

New Main Posts

14:40

1

Q: Compute the Matrix-Vector

Given an integer array of at least two elements, output the Matrix-Vector (defined below) of the array. To compute the Matrix-Vector, first rotate through the size-n input array to create a matrix of size n x n, with the first element of the array following the main diagonal. This forms the matr...

code-golf math array-manipulation matrix

Dennis

@LeakyNun There was a comment, but only for six minutes.

totallyhuman

Hey is there a use case in golfing where somebody would need to cast an int to a float?

Step Hen

How do you search for forward slash / in chat? (when combined with text)

Business Cat

@totallyhuman In CJam, / does integer division if both arguments are ints, so sometimes you have to cast one to double

Step Hen

ie /text in search currently searches for text, as far as I can tell

totallyhuman

14:52

@BusinessCat separate command for integer division so doesn't apply for intrnt

Business Cat

Then probably not

Usually the language would know e.g. 5 == 5.0

Step Hen

@BusinessCat that depends though, if floating point isn't exact some langs don't equate that

totallyhuman

!google Python custom class splat operator

Wait wrong chat room

AdmBorkBork

Jeez, @EriktheOutgolfer, save some languages for others. ;-p

Erik the Outgolfer

@AdmBorkBork sorry wrong person

:p

DJMcMayhem

16:35

→ 387 messages moved to Cryptic hunt

2

That's certainly a record.

Rahul2001

Lol :D

DJMcMayhem

I probably moved a few wrong ones in there, but there were so many I didn't want to bother to pick through them

Rahul2001

@DJMcMayhem It's okay :)

wizzwizz4

@DJMcMayhem They can always be moved back later.

Patrick Roberts

@programmer5000 Totally love your cops and robbers challenge. I'm looking forward to the reverse challenge as well: find the input that hangs the program. Suggested title "Just hangin'"

DJMcMayhem

16:55

Holy crap! I wrote up a solution, and then scrolled down to post it, but it turns out we wrote the exact same solution byte-for-byte! Even minor details like ({}[()]<{}>) vs ({}<{}>[()]) were the same! What a coincidence! — DJMcMayhem 29 secs ago

That was weird haha

Christopher

17:08

haha

CMC: unary (in number of zeros) to nullary

totallyhuman

hey i feel like i missed something in this challenge. can anybody find anything glaringly bad?

Christopher

@totallyhuman Answer my CMC and I will read it

totallyhuman

:P

i don't do unary or any bf derivatives like that

Christopher

...

totallyhuman

Ellipsis

totallyhuman

17:37

intput = lambda s:int(input(s))

Christopher

@totallyhuman wat is that

also why is it spelled intput

Cows quack

that's the devil called Python

Step Hen

@Christopher it gets an int input...

Christopher

@StepHen dumb

me

Dang it

@StepHen answer my CMC plez

Step Hen

@totallyhuman why are you passing s to input()?

@Christopher I dunno BF

Christopher

17:39

@StepHen don't need to

Business Cat

The argument to input is the prompt given to the user

Christopher

it has instructions on the URL of how to do it @StepHen

Step Hen

@BusinessCat oh duh I forgot since we're always golfing

Business Cat

Yes, sometimes it's beneficial for the user to understand the program

totallyhuman

although i should make it default to an empty string...

Business Cat

17:41

Except I put golfed code into my interpreter anyway

totallyhuman

intput = lambda prompt = '': int(input(prompt))

Business Cat

Like p=lambda s:[s[:1]+t for t in p(s[1:])]+p(s[1:])if s else [s]

I'll give a cookie if someone figures out what that does without running it

AdmBorkBork

I just had a chocolate chip cookie with Nutella and bacon on top, and I think I can feel my arteries clogging ...

9

Christopher

@AdmBorkBork O_O that sounds amazing

did you make it?

totallyhuman

that sounds scary tbh

>>> intput = lambda prompt = '': int(input(prompt))
>>> intput('halo enter number plz: ')
halo enter number plz: 42
42
>>>

AdmBorkBork

17:44

@Christopher No, from a food truck outside.

and yes, it was amazing

but oh so not good for ya

Christopher

@AdmBorkBork THEY HAVE FOOD TRUCKS WITH THOSE

I NEED TO MOVE

AdmBorkBork

Sure. The Twin Cities has a very rich food truck scene.

totallyhuman

"twin cities has" sounds so weird

AdmBorkBork

Yeah, it took me a while to get used to referring to the Twin Cities as a singular noun.

Christopher

Huh. I may actually be visiting there

I WILL FIND THAT CART

totallyhuman

17:51

truck

Xanderhall

Two php answers for challenges in a couple hours. Feeling good

totallyhuman

php is not the work of man

:P

Business Cat

Yesterday I used PHP for an answer solely because I needed PCRE

And Perl looks like BF

AdmBorkBork

@Christopher ramacsammys.com

Xanderhall

I have so much fun explaining php to new programmers

"What do you mean everything is a string"

Business Cat

17:53

PHP has the best worst features

Xanderhall

"What do you mean you can use a variable without initializing it"

Business Cat

I love that you can do $c = b; $$c = 5; echo $b; and it outputs 5

AdmBorkBork

@Xanderhall That's one of the things that keeps PowerShell competitive when it comes to golfing

Business Cat

Because that just makes perfect sense and is a totally useful feature

Xanderhall

"What do you mean $f = 'doSomething'; $f($input) works"

AdmBorkBork

17:55

also PowerShell, but not used very often for golfing

Xanderhall

not storing a function in the variable. Storing the name of the function, and then using that variable to call it

Christopher

@AdmBorkBork You are a beautiful person

Business Cat

Also $s = "test";echo ++$s; outputs tesu, 10/10 useful feature

AdmBorkBork

thanks

@BusinessCat OK, that's just weird

totallyhuman

lol

Xanderhall

17:56

@BusinessCat That feature is used for incrementing through string values. Think Excel

AdmBorkBork

When would PHP interface with Excel?

Xanderhall

for($foo = 'a'; $foo <= 'z'; $foo++)

Not saying it would, just saying it's kinda like Excel going through rows.

I did have to output a CSV file through PHP once, tho.

totallyhuman

` imgur.com/Br00TCn

Business Cat

I once used PHP to open a .xlsx as a zip folder and read the contents

Because why not ¯\_(ツ)_/¯

Transcript for