The Nineteenth Byte

Bubbler

00:00

huh

Bbrk24

> When a #if block is inactive due to os(), arch(), canImport(), a -D flag, or #if false, it's still parsed, but not compiled: example. However, if it's inactive due to swift(), it isn't parsed. It's tokenized so that the compiler knows where the correct #endif is, but it's not fully parsed: example. So, the fact that mismatched parentheses inside an inactive #if swift() do anything is bizarre, to say the least.

("example" were links before I copy-pasted :P )

thejonymyster

@thejonymyster no, this is optimal; UP is i/o, {} is necessary to take the entire input, ): is necessary to branch without discarding input/failing to output, N detects end of input... the only adjustable bit is ^D for accumulating the values, but thats the best way to do it, the alternative is ][] which is worse by over 100 points

Bbrk24

00:19

@lyxal Today in "Swift method names are painfully verbose": replacingOccurrences(of:with:)

tio.run/…

lyxal

that doesn't even sound grammatically correct

"replacing" should be "replace"

Bbrk24

no

you typically have func doingThing() -> Foo and mutating func doThing()

or, when the method name is a noun instead of a verb, func thing() -> Foo and mutating func formThing()

lyxal

$2.replacingOccurrences reads oddly though

Unrelated String

@Bubbler i just spent 10 minutes failing to realize that ⊙ literally pops the top and restores it afterwards, in the sense that if you break inside a ⊙ the top is not restored

Bbrk24

For some examples on Double: addingProduct vs addProduct and squareRoot vs formSquareRoot

So a hypothetical replaceOccurrences would mutate the string in-place

lyxal

00:25

but surely a better naming process could have been used

Bbrk24

And actually, the Objective-C class NSMutableString has replaceOccurrences

@lyxal Consistency with existing Objective-C APIs was a factor

lyxal

surely a better naming process could have been used for Objective-C

Bbrk24

Did you see the whole discussion about ObjC method names on Discord

lyxal

no

Bbrk24

> and the winner for “longest Objective-C method name” goes to…

initWithEnableFan:enableAirConditioner:enableClimateControl:enableAutoMode:airCirculationMode:fanSpeedIndex:fanSpeedPercentage:relativeFanSpeedSetting:temperature:relativeTemperatureSetting:climateZone:

Bubbler

00:28

lyxal

if that's the game they want to play then game on

OldSandboxPosts

01:00

Sandbox posts last active a week ago: (untitled)

Sandbox Posts

0

A: Sandbox for Proposed Challenges

code-golfmathcombinatorics Expected number of rounds for this labeling scheme Task Here is an interesting math problem: Let's say that there are \$n\$ indistinguishable objects in a bin. For every "round", pull \$k\$ objects randomly out of the bin with equal probability, and apply a label on ea...

noodle man

useless fact i learned today: if you look up "Elvis Presley Jailhouse Rock music video" you get this video by a channel called "y" with a single video and 209,000 subscribers

Unrelated String

happens

Aiden Chow

how to deal with floating point output in challenges, like should i say accurate to one decimal place or nah

Bubbler

01:36

10

A: Things to avoid when writing challenges

Real-valued output without further specification, or with a bad one For integer outputs, you can check correctness with exact equality. For exact fractions, many challenges require to output a (numerator, denominator) pair which has worked out pretty well in practice. But for real number outputs,...

tl;dr: never use "accurate to x decimal places", use "within absolute or relative error of 10^-x"

ATaco

I personally lean to being Far too lenient with floating point arithmatic, in a hope to not limit languages that don't support native floats. (Fixed point ftw)

thejonymyster

01:56

CMC: given distinct positive integers A and B, output all positive integers N where A mod N = B mod N

it was annoying me that it wasnt on one line on my device :P

ATaco

@thejonymyster What if A == B?

thejonymyster

distinct

so, that wont happen

ATaco

My b

thejonymyster

:P admittedly terse challenge wording, i just wanted it to be a one-liner

thankfully unambiguous though unlike my last attempted at a cmc (wah)

ATaco

Is this not just all the numbers from 1 to the lesser of A and B?

Unrelated String

02:04

@Bubbler done

thejonymyster

did i get it backwards or something

ATaco

I got it backwards

I did N%A, not A%N

thejonymyster

ok had me worried cause i did have to like, triple check to make sure i didnt make the same mistake lol

Bubbler

@thejonymyster some suitable golflang, 2 commands: absolute_difference divisors

thejonymyster

oh wow

ATaco

02:08

ARBLE, 24 bytes. range(1,A)&(eq(A%N,B%N))

I think that should work?

thejonymyster

assuming that code does what it looks like it does yea gg

i would not have considered the golflang solution though thats fun

ATaco

Almost works in ARBLE, though factors(abs(A-B)) doesn't output 1

thejonymyster

i wonder if you could just append it :P

@Bubbler can this generalize to a higher number of inputs?

ATaco

Oh you can, 1 ..factors(abs(A-B))

Or factors(abs(A-B))..1, is shorter, but I prefer my 1 at the start

Bubbler

@thejonymyster yes, map_on_neighboring_pairs{absolute_difference} reduce{gcd} divisors

thejonymyster

02:15

Oh my word

background; i thought of this question because i was wondering how tricky itd be to determine ahead of time which paths would have which major boss bloons in btd6 since some maps have multiple paths amongst which the bloons are divvied up, and they just added a map editor

Unrelated String

03:19

@UnrelatedString and now it's actually shorter in utf-8 bytes than the tag solution lmao

how the hell did i arrive at that tortured monstrosity, using constants for binary state, without realizing i could just use constants like dip

Aiden Chow

03:31

@Bubbler hmmm ok, got it

but how do strike a balance between reasonableness and being too lenient

becuz ok the thing is that the answers can be expressed in exact fractions, they are rationals

but

ik most langs dont have fraction data types

so, i am allowing floating point output

Bubbler

outputting (numerator, denominator) for rationals is often allowed

Aiden Chow

hmmmm ok but i want to allow floating point as well

cuz most langs wont have a fraction type to work with

Bubbler

for floats, 10^-6 for error margin is a good default

Aiden Chow

but now if u divide out the fraction it might not be exact

@Bubbler hmm ok

thats 10^-6 percent within the answer or what?

Bubbler

abs(true answer - calculated answer) / max(1, abs(true answer)) <= 10^-6

that is the definition of "absolute or relative error under 10^-6"

Aiden Chow

03:39

i have to put that whole formula into my challenge?

Bubbler

no, just using the english phrase is fine

lyxal

now that's a new one

that's very ironic

Aiden Chow

@Bubbler "You may output ... as a floating point number with a relative error under \$10^{-6}\$ from the true value" does this sound like good english

Bubbler

"absolute/relative", not just relative

looks good other than that

Aiden Chow

@Bubbler ok thanks

Newly Featured Posts

04:24

29

Q: Repeat your program to print Fibonacci numbers

Write a program fragment so that, when repeated N times it prints the Nth Fibonacci number. For example, if your program is print(x) then: print(x) should print 1 print(x)print(x) should print 1 print(x)print(x)print(x) should print 2 print(x)print(x)print(x)print(x) should print 3 print(x)print...

Unrelated String

oh wow thanks

mousetail

@Bbrk24 Feel free to (additionally) post any interesting solutions even if they are not the shortest

Bubbler

05:04

×τⁿπτ = 2021.789

surprisingly close but not too useful to get 2014

Command Master

05:47

What language is that?

Bubbler

Uiua

lyxal

06:57

-@ @߾

@Bubbler ^ for 6 bytes

tio.run/##K85JLM5ILf7/X9dBweH@vv//AQ for the raw text

The last character is chr(2046)

uiua.org/pad?src=LUAgQN--

Dannyu NDos

That's an N'Ko letter, apparently.

Neil

07:48

CMC: Given a string of printable ascii (space to ~), output a program that prints that string, but uses none of its characters. Both programs must use the same language and flags.

Bubbler

what if the input has the entire printable ascii?

ATaco

The Lenguage Meta-Cat works for this

Bubbler

hah

lyxal