The Nineteenth Byte

H.PWiz

00:33

Yours is better because it ends in normal mode though

New Sandboxed Posts

01:20

0

A: Sandbox for Proposed Challenges

Densely packed decimal (DPD) to decimal code-golf binary conversion Background Densely packed decimal (DPD) is a way to efficiently store decimal digits in binary. It stores three decimal digits (000 to 999) in 10 bits, so it is much more efficient than naive BCD (which stores one digit in 4 bi...

Pavel

01:34

@Adám Which version of Windows does this work on

Veskah

Hmm, anyone know off-hand if there's a challenge that simulates a cisco ios ping? I'm thinking have it be a 50% chance of packet loss, animate . or ! to the console for each tick, then output the percentage of success. Something nice and simple

lirtosiast

Not that I know of

FrownyFrog

@Pavel works on win7 here

lirtosiast

I wonder what the most important skill in code golf is

Obviously ability to solve the problem in the first place, ability to estimate whether an approach is short, fluency, working memory, knowledge of idioms, perseverance are all important

But is there one of those that especially distinguishes top golfers?

Veskah

01:52

Formula/Pattern spotting seems a big one. Key part in ASCII art and finding sweet mathy answers

Zacharý

@lirtosiast Occasionally even just knowing the syntax rules like the back of your hand if you're doing a more verbose language.

Veskah

@Zacharý True, knowing all the optimal ways to do some particular bit is usually good enough to get you 80% of the way there

lirtosiast

@Zacharý This is true, I don't think about it much because I usually use golfing languages

Zacharý

@Veskah Yeah, I was mainly thinking of me golfing other people's answers into oblivion.

(I mostly get that part in with suggesting golfs on people's answers in C/C++)

(There I can macro the thing to high hell)

lirtosiast

It seems like there are two aspects to code golf: optimizing particular snippets and finding the correct approach

Where the first is always important and the second gets more important as the problem gets harder (and solution space gets larger)

Veskah

02:49

Man, if someone posts a Duplicate link after like 10 seconds, I'm going to be butthurt

New Main Posts

1

Q: Simulate a Cisco Ping

Premise: For those in networking, you've most likely have had send a ping to or from something to make sure everything's properly connected. Cisco, a popular company in networking[citation needed], has a command for it in their IOS that looks like this: (Image source) Your challenge is to g...

Veskah

Are tags organized by popularity in the sub-header? It looks that way

Dennis

Yes.

Veskah

Now I fervently mash f5

Quintec

@Veskah You know that the page will show if there is an answer and you can click to see it right :P

Veskah

03:02

@Quintec It's just not the same

Quintec

@Veskah On the other hand, my F5 key changes the brightness of my MacBook keyboard :)

Veskah

Never a bad time for a rave

Quintec

@JoKing Congrats! And you just barely got that 200 reputation for the badge :)

lirtosiast

03:33

I wonder if the number of sandbox entries will ever catch up to the number of questions on this site

Veskah

@lirtosiast It might, but probably not for awhile. There's still enough off-the-cuff questions that can be chucked out without needing to refine it all that much.

lirtosiast

True

Downgoat

04:21

idea: a === b same as a = a == b

Bubbler

@Downgoat Extend it to !== <== >==

Veskah

We must go deeper, a ==== b

Pavel

So what you're saying is a != b should be a = a ! b

feersum

04:42

@lirtosiast Non-deleted sandbox entries, or total?

Bubbler

Or =!= =<= =>=, then we can also have =< and =>

feersum

Isn't ! unary? So you'd use it like a != menaing a = !a.

Adám

05:12

@Downgoat In Dyalog APL you can do a anyfn←b which means a←a anyfn b. E.g. a=←b a<←b a>←b a≡←b a×←b a,←b etc.

lirtosiast

06:36

@feersum Which one is the number below the question?

maxb

I have a question. Related both to this answer, this answer and this meta answer. Both of my answers in MathGolf end with ], which wraps the stack in an array.

Some people say that the wrapping is unnecessary since it only serves to format the output, while others say that since MathGolf's output format don't print the stack as an array, but as a joined string, I should keep the wrapping in array. What should I do? Should I save a byte but have output badly formatted, should I place the ] in the footer? Should I accept the extra byte for those solutions?

lirtosiast

I think you need the extra byte

The principle that languages are defined by their implementations overrides most others, and as it's currently implemented you can't distinguish 314 from 3, 1, 4

maxb

@lirtosiast That's a clearer answer, and it makes sense. It's not a huge loss, since I have used it to my advantage a few times. Thanks!

Downgoat

O_o why does a test case work when run individually but when run in test runner fails

maxb

06:55

@Downgoat What's the test?

Downgoat

07:05

@maxb for VSL , LLVM throws a “incompatible function argument types” error

For a test program very weird

github.com/vsl-lang/VSL/blob/upgrade-generics/test/class-field/…

maxb

@Downgoat Hmm, I can't say that I've worked with VSL before, but it does indeed seem strange.

Downgoat

08:01

even weirder: only occurs when run with other tests despite the fact each test is executed in an independent process.

Ooooohhhh has to do with dynamic libraries...

maxb

09:48

@Downgoat The obvious solution is to never use more than one process, ever. Just like the good old days of iPhone.

Skidsdev

11:14

I'm pleasantly surprised with how well my arbitrary randomness challenge was received

feersum

What I would like to see in such challenges is random bytes provided as an input.

Then (a) you can make the program deterministic, and (b) you can't shave time by using a crappier random engine.

maxb

11:29

@Skidsdev I am really excited for the fastest-code submissions. They always blow me away.

New Main Posts

11:43

0

Q: Kolmogorov Flexibility. A.K.A. Sale! \$38\%\$ Off All Codegolf While Stocks Last!

This is a restricted-source, kolmogorov-complexity, code-golf challenge to produce a fixed output with no input. The output format, however, is flexible - it may be printed to standard out, printed to standard error, returned as a list of characters, returned as a list of bytes, or returned as a...

code-golf kolmogorov-complexity restricted-source

New Main Posts

12:44

0

Q: Number of rotations

Task Write a function or a program to find the number of rotations required by a wheel to travel a given distance, given its radius. Rules Input can be 2 positive rational numbers and can be taken in any convenient format. Both inputs are of same unit. There must not be any digits 0-9 in you...

code-golf

Erik the Outgolfer

@NewMainPosts huh, I can't see any answers... must be that they're all whitespace

Adám

Do we have a generalised diagonal challenge? I.e. return the list consisting of elements [0,0,…,0], [1,1,…,1] … [k,k,…,k] of a size kⁿ, n-dimensional array?

Fatalize

13:01

@Adám Don't think so but I'm not sure I understand your spec

Adám

@Fatalize Maybe an example can help: [[[1,2,3],[4,5,6],[7,8,9]],[[10,11,12],[13,14,15],[16,17,18]],[[19,20,21],[22,2‌3,24],[25,26,27]]] → [1,14,27]

Fatalize

I see

Erik the Outgolfer

and I thought k and n are the inputs, not the array itself :P

Adám

It can possibly be made more interesting by not guaranteeing dimension lengths, e.g. [[[1,2],[3,4],[5,6]],[[7,8],[9,10],[11,12]],[[13,14],[15,16],[17,18]]] → [1,10]

@EriktheOutgolfer That's an alternative challenge. :-)

Erik the Outgolfer

@Adám well... actually, I at first thought that the word "diagonal" was used in error over there

like, a completely different challenge

Adám

13:11

@EriktheOutgolfer Not really. I.e. {"n":4,"k":3} → [1,41,81]

Erik the Outgolfer

@Adám no, not this, something else

Adám

@EriktheOutgolfer Then what did you understand?

Erik the Outgolfer

@Adám for example, k = 4, n = 2 → [[0, 0, 0, 0], [1, 1, 1, 1], [2, 2, 2, 2], [3, 3, 3, 3]]

Adám

@EriktheOutgolfer What does k=2 n=3 give?

Erik the Outgolfer

@Adám [[[0, 0], [0, 0]], [[1, 1], [1, 1]]]

I know, very messed up

Adám

13:14

@EriktheOutgolfer OK, that's… odd.

The major cells are full of one of ⍳k each, and the shape is n⍴k?

Erik the Outgolfer

@Adám more like ⎕IO←0⋄(⊃I)≡I⌷x, (n⍴k)≡⍴x (where x is the result)

and, of course, n≡⍴I and ⎕IO←0⋄∧/I∊⍳k

Adám

n(⊢∘⍳+⍤0 ¯1⍴⍴0××)k

Erik the Outgolfer

@Adám 0×× can be {0} (same length), no?

Adám

@EriktheOutgolfer Yup, I just thought it was fun to throw some math in there. I hope to get 0⍨ accepted for 18.0.

0⊣⊢ works too, and a bunch of others.

Erik the Outgolfer

btw, I have a 5-byte solution for the diagonal challenge, although I won't show it yet

Adám

13:25

@EriktheOutgolfer Nice. I only have 6

Maybe it would be better to do the k,n→d as the test cases will be much more compact?

maxb

@Adám \\#(\_(?\/\r\*) solves that case, I haven't tried any other cases, but I think the logic holds. When I get my current changes up to TIO I could probably knock off 2-4 bytes.

Erik the Outgolfer

@Adám clueless prediction: from there, you need a bit of thought before the snap comes :P

Adám

@maxb Cool, but hold your ~~Buddhas~~ horses, I may main it.

@EriktheOutgolfer Got 5, but doesn't work on empty arrays, and requires ⎕IO←1.

Erik the Outgolfer

@Adám yep; although empty arrays are edge cases

Adám

@EriktheOutgolfer True, and shouldn't be included in the actual challenge since many languages (including JSON) can't.

@EriktheOutgolfer Get the joke ^?

Erik the Outgolfer

13:34

@Adám yeah, those empty array jokes :P

Adám

@EriktheOutgolfer :-⍬ or should it be :- ?

Erik the Outgolfer

uh... what kind of tongue formation is that

(yes, it looks like some yucky tongue formation at first)

Adám

Skidsdev

13:54

I'll be running whatever answers exist so far on my fastest-code challenge tonight to give their actual scores

New Main Posts

16:02

1

Q: Find the best period in which to have invested in a S&P500 index fund

Here are the annual returns for a hypothetical S&P 500 stock index fund for each calendar year from 1928 to 2017, expressed as a multiplier. So in 1927 you might say "the index went up by 37.88%" which I've represented here by 1.3788. 1.3788, 0.8809, 0.7152, 0.5293, 0.8485, 1.4659, 0.9406, 1.413...

code-golf

Pavel

16:49

Java 12 to introduce `raw strings`

openjdk.java.net/jeps/326

Also, Switch expressions: openjdk.java.net/jeps/325

And C#-style cast-check (simple pattern matching): openjdk.java.net/jeps/305

Zacharý

17:07

Hello, Java-not-script

Sorry, forgot editing a reply pings.

Erik the Outgolfer

Um, it looks like there are 90 integers in there, not 89. — Erik the Outgolfer 30 mins ago

so, I said "integers"

Zacharý

What is this in response to?

ngn

@EriktheOutgolfer @Adám ⍴⍴0×× can be 0⍴⍨⍴

Erik the Outgolfer

@ngn how?

Adám

@ngn No, clashes with ⍤'s operand.

ngn

17:16

ah...

Erik the Outgolfer

yeah, that was my concern

ngn

@Adám is n=0 valid input?

if not, ⍴⍴↓ could work

Adám

@ngn Erik's challenge.

ngn

@EriktheOutgolfer ^

Erik the Outgolfer

yeah, hm

it's an edge case

lirtosiast

17:29

@Adám No generalized diagonal challenge I can find; I checked when posting dyadic transpose

ngn

@Adám the 0 in +⍤0 ¯1 seems unnecessary

it could also be +[0] (except for n=0)

and isn't the whole thing just ⊃¨∘⍳⍴

ETHproductions

17:53

Would it be a good idea to have a community wiki answer on restricted-source challenges to collect the languages that cannot solve the challenge? (e.g. Find an Illegal String could probably use one)

And has this been asked/done before?

J. Sallé

@ETHproductions sounds like a good meta-question to me

Zacharý

Well, if it's provable, then I'd say so.

J. Sallé

@ETHproductions couldn't find any post in meta relating to this specific question

Zacharý

Oh, and hello Ð.

ETHproductions

Hello ý

@J.Sallé Thanks, I'll write one up then...

Zacharý

18:24

LOL.

Adám

@ETHproductions Nope, CW doesn't allow breaking rules.

If ETH is Ð and Zacharý is ý, am I á?

ETHproductions

@Adám Hmm. Well, the other idea that came to mind while writing it up was a separate answer for each language--like a regular answer, but proving impossibility instead. I suppose that would be against the rules as well?

Adám

@ETHproductions Yes, but why don't you write a proof-golf challenge for it?

Zacharý

@Adám Yeah, I'd assume so.

ETHproductions

@Adám Now there's an idea--a proof-golf challenge for proving something is impossible in your language of choice :-) Not what I was going for though; I just want to somehow establish that the optimal solution in a given language is no solution.

Adám

18:38

The first letter of Οurous is not O. I guess that's why @ auto-completes to that — to make it easier to ping with a standard keyboard.

Zacharý

It's capital Omicron, if I remember correctly.

Adám

@Zacharý Yes.

Zacharý

Woah, that's nice functionality.

Adám

@Zacharý So far, I only support Upper circled Latin, upper and lower Latin, Cyrillic, and Greek, plus normal, superscript, and subscript digits.

Zacharý

@Adám Otherwise it acts weird

Adám

18:54

@Zacharý Yeah, it will give you from the closest starting point of any of those.

Skidsdev

hah I like that windows 10 turns 2 of those into emojis

they stand out

(namely ⌚ and ⌛)

Zacharý

Linux as well, my friend

Skidsdev

I mean with linux it depends on what system font you have installed

sorry to be clear by turns them into emojis I mean shows full color icons for them

Adám

⎕ucs 65038 to the rescue…

FrownyFrog

weirder

Zacharý

18:56

Bug fix?

Adám

mojibake

Zacharý

wait, what?

ETHproductions

@Zacharý looks like UTF-8 converted to ISO-8859-1?

Zacharý

Yeah...

Adám

Off-topic question: What is the most precise moment in time that is considered "significant"?

ETHproductions

19:01

I think the Big Bang counts as "significant"

Skidsdev

define significant

ETHproductions

or is that not what you're asking?

Skidsdev

I think adam means smallest measurement of time

ETHproductions

oh, then the Planck time perhaps?

Zacharý

PLANCK

(sorry caps lock, and ninja'd ...)

Skidsdev

19:02

Second: The time needed for a cesium-133 atom to perform 9,192,631,770 complete oscillations.

FrownyFrog

planck mass is funny

Skidsdev

so 1 oscillation of a cesium-133 atom?

FrownyFrog

it’s about 1 flea's egg

Adám

No, I mean, most famous moments in history are known by their dates. Occasionally something happened at a specific hour.

Skidsdev

Oh okay

Adám

19:03

The best I've found so far was Apollo 11's Moon landing, known to the (relativity!) second.

Skidsdev

that's probably more precise than my suggestion

which was the signing of the world war 1 armistice

Adám

@Skidsdev Most people take more than a second to sign something.

Skidsdev

right but you could determine the exact second pen hit paper, but I don't think we know that exact second

or the exact second the signing was complete, at which point the armistice came into effect

Adám

@Skidsdev Exactly my point. So what is the most precise "significant" moment we do know?

Skidsdev

I think we only know it to the hour though

"The eleventh hour of the eleventh day of the eleventh month, 1918"

Zacharý

19:06

Adám

Maybe we know the millisecond the LHC made its first collision?

Skidsdev

maybe

AdmBorkBork

How about when a leap-second was added to clocks that couple years ago? That had to be very precise on NIST's part.

Adám

@AdmBorkBork Ah, the very first leap-second?

Skidsdev

do we know that to the millisecond though? Trouble is with things like that, it could take longer than a single ms to actually happen

Erik the Outgolfer

19:09

not sure if leap seconds are considered significant, apart from the first

Skidsdev

LHC collision could probably be accurate to the nanosecond, but I don't think we measure that precisely

Adám

First leap second was Jun 30, '72 at 23:59:60.000 UTC (by definition?)

ETHproductions

@Adám Here's a question related to mine. The difference is that this one talks about generally impossible challenges, not just im/possible per-language. Couldn't find one about per-language.

AdmBorkBork

Oh, I got one - how about when LIGO first detected gravitational waves?

I think that's on the order of ms

ETHproductions

We could probably find the moment of the first commit to the Linux repo down to the millisecond, if the full history exists somewhere online

The repo on GitHub only goes back to 2005-04-16T22:20:36Z

Skidsdev

19:16

So I noticed nandgame linked in the chat pins, and in my attempt to create an or gate, I accidentally created a nand gate...

Adám

@ETHproductions Linus Torvalds released Git four years after he released Linux, so that kind-of makes sense. The date you have is just a week after Git was released.

ETHproductions

...wow, I totally forgot to take that into consideration xD

Skidsdev

@ETHproductions afaik git relies on unix timestamps, which is only accurate to the second

ugh can somebody give me a hint on how to build an OR gate using only AND, NAND and NOT? :P

Adám

@Skidsdev Right.

ETHproductions

@Skidsdev You can do NOT on the output of an AND gate

Skidsdev

19:21

@ETHproductions jesus christ I'm an actual idiot

Erik the Outgolfer

but that's NAND

(literally NOT AND)

Skidsdev

No it isn't

well yeah but no

Or wait no, I'd need to NOT a NAND gate

Adám

@Skidsdev Hint: OR is false when p∧~q and when p∧q and when q∧~p

ETHproductions

@EriktheOutgolfer wow, I'm an actual idiot :P

Skidsdev

because a NAND gate is only 1 on 0 and 0

we want the opposite of that (1 on anything but 0 and 0)

@Adám you lost me after the first when

Erik the Outgolfer

19:22

@Skidsdev false

ETHproductions

@Skidsdev start by doing NOT on both inputs

Erik the Outgolfer

NAND is only 0 when its inputs are both 1

Skidsdev

@EriktheOutgolfer ok correction, NAND is only 1 on 0 and 0 in this game

Adám

@Skidsdev Just translate exactly that!

Erik the Outgolfer

@Skidsdev that's NOR

Skidsdev

19:23

that's an OR

ETHproductions

NAND gate

In digital electronics, a NAND gate (NOT-AND) is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs to the gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results. A NAND gate is made using transistors and junction diodes. By De Morgan's theorem, a two-input NAND gate's logic may be expressed as AB=A+B, making a NAND gate equivalent to inverters followed by an OR gate. The NAND gate is significant because any boolean function can be implemented...

Skidsdev

yeah wel, this game also calls NOT "inv" so.. yeah

Erik the Outgolfer

but it doesn't have bugged NAND gates

Skidsdev

oh no nevermind you guys are right, this game is correct about NAND

I am still an idiot

ETHproductions

I've always wondered how the NAND gates output an electrical signal when given 0 and 0... now I see they just have a power input as well, lol

Adám

19:24

∨≡~⍢~

Skidsdev

haha, yes

ETHproductions

I'm such a noob at electrical engineering, though much less of one after playing this game :-)

Skidsdev

@Adám ~ is not right? Is ^ and?

Adám

@Skidsdev Yes, in standard formal logic notation (and in APL)

Skidsdev

no wait & is and, is ^ NAND?

oh

ok yeah that's the set up I already had

my problem then was merging all 3 inputs

AdmBorkBork

19:26

Electrical engineering: Every machine is a smoke machine if you operate it wrong enough.

3

Skidsdev

because nandgame only lets each input node link to 1 output node (although a single output node can link to multiple input nodes)

so then I'd need to somehow OR all 3 of those results to get my answer

Adám

@Skidsdev a∨b∨c

Skidsdev

what's v? NAND?

Adám

OR in standard formal logic notation (and in APL).

Erik the Outgolfer

@Skidsdev well... how many wires go to one input? :P

Skidsdev

19:27

Yeah but I don't have OR, that's the whole point. I'm trying to create OR using only NAND, NOT and AND

I got it anyway, it's ~a NAND ~b

Erik the Outgolfer

it's pretty easy if you think a little bit, I'm sure

yay!

hint: use truth tables

Skidsdev

yup :P

hmm now xor

Zacharý

If you've got and, or, not, it should be easy.

Erik the Outgolfer

not isn't necessary if you have nand

Adám

@EriktheOutgolfer Obviously, that's the entire game. Is there a norgame too?

Zacharý

19:31

I've been fine with the logic part of electrical engineering (what the game is based off of) but the wiring and grounding and all that ... never been good with it.

@EriktheOutgolfer Nothing else is necessary if you have NAND :P

Skidsdev

yeah that's the whole point of the game, you start with just a NAND and have to construct all the other gates

thankfully once you construct another gate it gives you that gate

Erik the Outgolfer

no, I mean, you don't even need to craft a NOT gate for XOR

Skidsdev

right

so if ~ is NOR, ^ is AND and v is OR, what's NAND? ~^? :P

Adám

They should totally make a norgame.com (only the first few steps will be different), just to make the point that either is sufficient.

@Skidsdev Yes ⍲.

Skidsdev

ooh

Adám

19:33

@Skidsdev Now can you guess NOR?

Skidsdev

ok so (AvB)^(A⍲B) gets me XOR

uh.. a compond symbol of ~v?

Adám

@Skidsdev Yup; ⍱.

Erik the Outgolfer

⍱

Skidsdev

oh good I know how to make a half adder :D

Adám

@Skidsdev Can you guess XOR?

Skidsdev

19:35

hmm

see in C# (and I think JS and Java), XOR is ^

Adám

@Skidsdev Try looking at the truth table and see if you notice a pattern.

@Skidsdev That's just silly, when ∧ is the real symbol for AND.

Skidsdev

is XOR a combination of NOR, NOT and AND?

Adám

@Skidsdev No, the truth table is

0 1
1 0

Zacharý

`8

Adám

@Skidsdev So what relationship is there between A and B for XOR to be true?

Skidsdev

19:37

a and ~b or b and ~a

Zacharý

(Think outside of ∨, ∧, and ~)

Adám

@Skidsdev Yes, so A and B are _______? (in English)

Skidsdev

opposites?

inverted?

Adám

@Skidsdev Are A and B the same value when XOR is true?

Skidsdev

no

oh is it the not equal sign? The equals with the slash through it?

Adám

19:40

@Skidsdev Exactly! ≠

Skidsdev

the one that I can't type because I don't have a numpad to do altcodes :P

woo!

Adám

@Skidsdev And how about NXOR? (a.k.a. XNOR for some strange reason)

Zacharý

javascript:(d=>{let%20e=d.createElement("script");e.src="https://abrudz.github.i‌o/lb/lb.js";d.body.appendChild(e)})(document)

Skidsdev

=?

Adám

@Skidsdev Yes!

@Skidsdev What Zacharý is trying to say is that you should visit this page.

Skidsdev

19:42

oh yeah I had that on my old PC from when I started to learn APL

there we go

lmao I'm thinking back to minecraft to remember how to build a full adder

Adám

So a neat thing: you can "play" NandGame in APL. E.g. inv←⊢⍲⊢ (NAND with both connectors going to the same side), and←inv⊣⍲⊢, or←(~⊣)⍲(~⊢) etc.

dzaima

@Adám yeah, the last thing in my dyalog repl is an xor gate made out of trains & ⍲ :p

Adám

You can even set up an oscillator clock with ⎕FX'c←c' 'c←2|6⊃⎕TS'. Now if you continuously query c you'll see that it switches between 0 and 1 every second.

@dzaima trains and ⍲ or trains of ⍲?

dzaima

@Adám trains of ⍲ (and ⊣ & ⊢ because you can't trains without them)

Skidsdev

oh boy

Adám

19:54

@dzaima Right, and then if you built it step by step, you can query its value (with ]box on -t=parens) to get its entire definition just made of (⊣⍲⊢)

Skidsdev

the game just jumped from "Great you figured out how to add 2 2-bit numbers with a carry, now let's do 16-bit"

ETHproductions

@J.Sallé Posted. (cc @Adám)

dzaima

@Skidsdev yeah, i felt like it needed an intermediate step there, at least by showing how the adders get chained up (not that it's very important or anything, but still)

Erik the Outgolfer

@ETHproductions why not just make it "a challenge" in general?

ETHproductions

@EriktheOutgolfer Just thought of that myself, thanks.

Skidsdev

20:00

oof, reached my first level where I didn't get the minimum possible

Zacharý

It gets worse from there, friend

Skidsdev

oh no, got it down from 9 to 7 but it can still be done smaller

hmm ok, b if a else c

New Meta Posts

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Q: What should we do when a language cannot answer a given challenge?

Many challenges, mainly restricted-source, are impossible in some languages. Find an Illegal String is a good example—many languages without syntax errors, such as brainfuck (deleted answer), can simply be put in an infinite loop before the illegal string is reached within the code. The challenge...

discussion answers

Mr. Xcoder

20:51

CMC: Let X1, X2, X3, …, Xn be a list of integers given. Output the product Y1 * Y2 * Y3 * … * Yn, where Yk is the lowest natural number whose prime factors are the same as Xk's (that is, without counting multiplicities)

Note that this is unbelievably short in 05AB1E...

Adám

@Mr.Xcoder Yk is?

Mr. Xcoder

@Adám Yk for each 1 ≤ k ≤ n.

k is an index.

Adám

@Mr.Xcoder Ah, ok.

Erik the Outgolfer

@Mr.Xcoder Jelly, 6 bytes: ÆfQ€ẎP

Mr. Xcoder

@EriktheOutgolfer Nice, an equivalent: ÆFZPPḢ

Pavel

21:10

Super dissapointed this doesn't work

Erik the Outgolfer

because that's not a class, but an imported module

also, classes need instantiation too

quartata

you could probably do it with a metaclass

hmm actually

Pavel

@EriktheOutgolfer Right. It doesn't work if I remove the self parameter, either

Modules in python are "normal" objects

Erik the Outgolfer

actually, they're special

quartata

can you hook into the creation of a module like that

probably not

Pavel

21:15

The ideal is to be able to define __call__

So if your module only has one method in it

You can call the module directly

I'm actually curious why it doesn't work, though. Is + special-cased to check for modules?

Erik the Outgolfer

well, you can't actually make an instance of a module

Adám

21:31

@ThomasWard How much work is it for a mod to clear the stars from many consecutive messages?

Thomas Ward

i'd have to clear them per message, which ones need hosed?

Adám

@ThomasWard Then I (RO) can do it myself. Thanks!

Thomas Ward

ok

@Adám alternatively we can just nuke the room and begin again but for obvious reasons you probably DON'T want to do that :P

Adám

@ThomasWard No no.

Thomas Ward

that's what I thought :P

Adám

21:42

@ThomasWard All done. Wasn't that bad. The confirmation prompts are annoying though.

Thomas Ward

indeed

flawr

22:06

@ThomasWard how are your eyes doing?

Pavel

Currently undergoing LASIK?

Adám

22:35

Today's XKCD so applies to me. ⍨

Veskah

Same, only update site information when actually forced to

Adám

@Veskah My bank refused to update my address when they found out that my old address was missing the flat letter.

flawr

@Adám so now you still have your old adress?

Mr. Xcoder

It applies to me too when I order pizza in particular lol

Veskah

No, he had to buy the entire apartment building @flawr

Adám

22:42

@flawr At the bank yes, but my wife (we have a joint account) managed to move her address to our new actual place.

flawr

@Mr.Xcoder Have you registered your adress on a pizza delivery service?

Mr. Xcoder

They've done it automatically :)

Adám

I asked the bank what would happen if I just close the account. They said they'd send a cheque with the remaining balance. I wonder where they'd send it…

flawr

hehe

Erik the Outgolfer

banks are over-complicating things...

Mr. Xcoder

22:44

Citing my maths prof., if you enter a bank you're surely going to lose money :P

... and time

Nathan Merrill

That's why I use an online bank.

no need to enter anywhere :)

Adám

That's the same bank that refused to let me cancel my loan because of that missing letter in the address, so I had to keep paying interest even though I had already paid back the entire loan.

Mr. Xcoder

O_o

Adám

@NathanMerrill That's what I'm planning on switching to, but it's just so complicated to do so.

Nathan Merrill

yeah, I'm actually in that process right now.

The biggest hold up is my wife: she gets (justifiably) worried whenever big things happen around money

so we're slowly transferring accounts over

Adám

22:48

How comes I have two Visa cards with the same card number, different expiration dates and different 3 digits on the back? Does that mean that multiple answers to those two things are valid for a single card number?

Nathan Merrill

I've never heard of that

Adám

And yes, both cards are functional, and no, I did not report my card lost.

Veskah

Bank renewed my card which was same number ,diff exp dates and security code. I think they were both valid during the overlap of ordering it in the mail and getting it

Adám

@Veskah Ah, OK, thanks.

The older card's magnetic stripe is gone, so I primarily use that; in case I loose it, it can only be abused for small contactless amounts .

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