The Nineteenth Byte

Григорий Перельман

4:00 AM

strawpoll.me/12575246

ATaco

If I knew how to make the Results of the Strawpoll automatically Update, I would.

Jan Dvorak

That's easy: use a decent browser

Григорий Перельман

No, in the userscript onebox.

Jan Dvorak

Is there one?

ATaco

Strawpoll's results don't appear to automatically update when embedded, my two solutions to that is either: Just use the API and write my own interface, or try to find out why.

Jan Dvorak

4:05 AM

The latter sounds like a better choice

ATaco

Apparently results do automatically update, I guess it's just hard to test.

For a brief test, please vote NO to this poll. (I know sandbox is for testing please don't shoot me)

strawpoll.me/12575274

I can confirm, it does update live.

Apparently there used to be an issue with using an HTTPS connection, which I couldn't not use if I wanted to (Firefox doesn't like using HTTP IFrames in an HTTPS Environment)

github.com/TehFlaminTaco/TacosUserscripts/blob/master/…

For those who want the Userscript.

I can confirm, Staring a OneBox'd Strawpoll does not create sadness.

Mendeleev

4:21 AM

@ATaco Yes, you would have to look at it really hard

Григорий Перельман

CMC: Calculate 20^(5*6^69)

No hard coding

ATaco

RProgn 2 $20 56*$69^^

Destructible Lemon

that's a big number

Mendeleev

@ГригорийПерельман Ruby: p 20**(5*6**69)

Григорий Перельман

Must be able to finish on a normal machine without getting ended by the OOM-killer.

I'll say nothing about time.

ATaco

4:26 AM

It's returning 1, so I may have screwed up somewhere.

I'm not sure RProgN2 can handle indices of such ridiculous size.

It simply does not, this is far too large for it to hope to accomplish.

Григорий Перельман

The idea is that it's so huge you can't just use normal math, you have to use a smarter system.

ATaco

Also, the Ruby Solution fails, returns Infinity

user165474

question: Who else here is from timezone EDT?

Mendeleev

@ГригорийПерельман I can use modular exponentiation bindings

ATaco

1x=$20{56*$69^}*){x*`x=};x

THERE we go.

1x=$20{56*$69^x*`x=}*x golf'd.

And yes, RProgN2 does handle this stupidly big number very quickly.

Григорий Перельман

4:33 AM

@Mendeleev Sure, works.

Mendeleev

Ruby: a=20;(5*6**69).times{a*=20}

ATaco

In .03 seconds, infact.

Mendeleev

Will take approximately forever

ATaco

.03 seconds is much faster than Ruby.

Mendeleev

> I'll say nothing about time.

ATaco

4:34 AM

Oh, I'm doing this upside down.

I'm doing n^20, not 20^n. Hold on.

Григорий Перельман

@ATaco Noice.

How does that work?

ATaco

1x=56*$69^{20x*`x=}*x is actually correct.

Although takes approximately forever.

Григорий Перельман

Yep

Does it run out of memory?

ATaco

Nope.

Well, if it's on a machine that has enough Ram to store the number it doesn't.

Григорий Перельман

Cool.

ATaco

4:38 AM

Otherwise, I need to answer in Base20.

Григорий Перельман

Advanced CMC: Do it in a way where it can be actualy run.

I might make this a fastest-code challenge.

ATaco

1w56*$69^{0w}* gives the answer in an unknown large amount of time in Base 20.

Mendeleev

CMC: Print "Hello, World!"

ATaco

"Hello, World!", Like, 30 languages.

betseg

APL, 'Hello, World!'

ATaco

4:41 AM

@ГригорийПерельман That is literally un-testable, as it requires an output greater than the amount of atoms in the observable universe.

Григорий Перельман

But the number itself fits.

ATaco

Not in Base 20, not in base 10.

Григорий Перельман

Wait, how big is this number really? I might be underestimating it somewhat.

Mendeleev

@ГригорийПерельман unimaginably big

ATaco

Well, (5*6)^69 is...

83438516833108053377185732869528300000000000000000000000000000000000000000000000‌0000000000000000000000

betseg

4:43 AM

WolframAlpha says that the number is about 10^10^54.5

ATaco

10^(5*6)^69 is 1 followed by that many 0's.

Which, on it's own, is nearly a Googol.

Григорий Перельман

Well, crap.

ATaco

There are approximately 10^120 atoms in the observable universe, by the way.

betseg

I thought 10^80?

ATaco

Shannon number is 10^120.

And I'm not sure how that relates now that I look at it.

4x10^79 is more correct.

Which means the difference of just 10, not 20, is a magnitude of 834385168331080533771857328695287999999...50~

Григорий Перельман

4:46 AM

CMC: Calculate the number of digits in that number when expressed in base 10.

ATaco

10^54.5

Mistah Figgins

@Mendeleev There is a challenge for that

ATaco

10000000000000000000000000000000000000000000000000000000

Mendeleev

@MistahFiggins ik

Григорий Перельман

Bah, I'm tired.

ATaco

4:47 AM

Wait, but it's 83438516833108053377185732869528300000000000000000000000000000000000000000000000‌‌0000000000000000000000 in base 20?

Wolfram Alpha cannot actually do the math required at that strange level.

10855601319358759265348844436018082996981833802803715980120000000000000000000000‌000000000000000000000000000000000000000000000000000000000000000000000000000000000‌0

I did the math myself.

That many digits.

This number is Unfathomably huge.

I could explain it in relation to atoms in the observable universe, but it does not matter, the human mind actually cannot comprehend how big this number is.

betseg

We're used to 10 fruits and 3 animals in forests. Not these numbers.

Jan Dvorak

I really hope you mean species, not specimen

Mendeleev

^

Григорий Перельман

CMC (again)
Find the lowest base where the final number can reasonably fit on a screen.

This does not have to be exact.

Mendeleev

@ГригорийПерельман 1

betseg

4:59 AM

Explain "reasonably fit on a screen"

Mistah Figgins

Well, depends on what you mean by "fit" and "screen"

You could have black and white pixels be binary on a large tv screen

ATaco

Base

1085560131935875926534884443601808299698183380280371598012000000000000000000000‌0‌000000000000000000000000000000000000000000000000000000000000000000000000000000‌000‌0

would pretty reasonably fit.

"10"

Mendeleev

@MistahFiggins Each pixel is 24 bits, on an 8k screen

Mistah Figgins

@ATaco it's not pretty though

ATaco

Fits Pretty well for me.

Google's prettifier starts to not work too well at lower monitor sizes.

New Sandboxed Posts

5:03 AM

0

A: Sandbox for Proposed Challenges

Divide and divide and conquer Sometimes, when I'm idly trying to factor whatever number pops up in front of me¹, after a while I realize it's easier than I thought. Take 2156 for example: it eventually occurs to me that both 21 and 56 are multiples of 7, and so certainly 2156 = 21 x 100 + 56 is ...

Mistah Figgins

Wow, the first strategy mentioned is completely new to me. I hadn't thought about it that way before. huh.

ais523

5:20 AM

hmm, I managed to get Necromancer for an answer to my own question, that's been continuously active (it's the polyglot question, it needs to have an answer every 14 days by its rules)

something seems wrong with the definition of the badge there

(perhaps it should be checking for a question that's been inactive for 60 days, rather than just being 60 days old)

Jan Dvorak

You could post a FR on MSE

ais523

not sure it's really worth it, implausibly granted badges don't really harm much

I was just amused

New Main Posts

5:37 AM

0

Q: Number to words based on the dictionary

Given a 10 digit phone number, you must return all possible words or combination of words from the provided dictionary, that can be mapped back as a whole to the number. With this we can generate numbers like 1-800-motortruck which is easier to remember then 1-800-6686787825 The phone number map...

ruby

Mistah Figgins

5:57 AM

CMC: convert keys to uppercase. This includes non-letter keys such as 5 -> %, or ] -> }

Use the keyboard you have, or an otherwise popular (not-obscure) one

ais523

hmm, this question makes me more certain in my opinion that golfing languages should have a builtin for the entire QWERTY keyboard, not just the letters like Jelly

betseg

I can't use my keyboard for this CMC :/ shift+i=İ

ais523

you have a Turkish keyboard?

betseg

Yes

ATaco

Do we need to support >?:"?

And such?

betseg

6:02 AM

> This includes non-letter keys such as 5 -> %, or ] -> }

ATaco

Oh...

ais523

are you Turkish? or did you just get given an unusually-layouted keyboard for some reason? for a while I ended up working on an AZERTY keyboard (left by a previous employee) even though I'm in an English-speaking country

ATaco

Also, I'm using a custom keyboard to Type RProgN2.

betseg

@ais523 I'm Turkish

ATaco

Almost entirely so I can type «»‹›

@MistahFiggins What about DeadKeys? US-INTL does not handle Shift-' as a single character.

New Main Posts

6:12 AM

0

Q: Shortest code that throws SIGBUS

We've had challenges for SIGSEGV and SIGILL so why not... Write the shortest code that results in a Bus Error (SIGBUS) in any programming language.

code-golf

orlp

guys remember to never go to the north pole

things can only go south from there

Jan Dvorak

groans

betseg

i saw that too

Григорий Перельман

@orlp I am profoundly disappointed in you.

That was terrible.

Like, it's around hotdog.vim levels of terrible.

betseg

reddit.com/r/AskReddit/comments/60ivao/…

CMC: open this xkcd without import antigravity

Jan Dvorak

6:31 AM

done

betseg

:(

CMC: open this xkcd using a programming language without using import antigravity and post the source code here

ASCII-only

JavaScript (ES6), 39 bytes: window.location='https://xkcd.com/353/'

Jan Dvorak

Powershell: start-process http://xkcd.com/353/

ASCII-only

Command Prompt, 27 bytes: start https://xkcd.com/353/

Linux, 30 bytes: xdg-open https://xkcd.com/353/ (I think, can't test atm)

betseg

Bash with Xorg, 29 bytes: `xdg-open htt

ninja'd

ASCII-only

6:43 AM

Oh wait the trailing slash can be shaved off all of them

And the s in https

JavaScript, 28 bytes: location='http:xkcd.com/353'

betseg

Bash with Xorg, 27 bytes: xdg-open http:xkcd.com/353

no need for //

Anonymous

@betseg __import__('antigravity')

Mendeleev

Bash/OSX: open http:xkcd.com/353

betseg

18 mins ago, by betseg

:(

Anonymous

Phrase your rules better :P

Anonymous

6:50 AM

python -mantigravity

betseg

third CMC: open this xkcd using a programming language without using the antigravity module and post the source code here

Jan Dvorak

Bash and Powershell are programming languages...

betseg

yes?

Mendeleev

@betseg Ruby on OSX: `open http:xkcd.com/353`

numbermaniac

7:07 AM

@Mendeleev also works in bash on macOS

Mendeleev

7:41 AM

@ГригорийПерельман you might like this youtu.be/ncNzFwWGRto

Stewie Griffin

@Sp3000 You've been beaten! You were right though: "[...] I wanted to play off the idea that, once you have enough languages, byte count doesn't matter as much any more"

New Main Posts

0

Q: Visualize nested array

You will be given a nested array. Your program has to visualize the array. But.. How? For example, let's assume we have a nested array, like [["1","2"],[["1","2"],"3"]]. This nested array can be visualised as: >1 >2 ->1 ->2 >3 Examples Input 1: ["Atom",["Proton",["Up Quark", "Up Quark"...

code-golf

Destructible Lemon

> Come November 1, Programming Puzzles and Code Golf will graduate, so in the next 11 months, we'll want to save some memories from when we were ungraduated.

From the make the PCG logo

why SE why

betseg

we will have our design as a april first joke right?

Fatalize

8:01 AM

@DestructibleLemon "Make the PCG logo" ?

New Main Posts

8:44 AM

0

Q: Short python code for find out even and odd number

Could anyone please help me to find out how to write down that below quiz by python code? I try to figure out the answer by myself, but I couldn't understand how to find even and odd number from x to y that is not int. Please help me. Menu-driven number sequence generator: A school teacher re...

code-golf python

Stewie Griffin

6

^^Voted to delete!

Welcome to PPCG! You should know that answers that provide little or no explanation get automatically flagged by the system and end up in the Low Quality Review Queue. Note that if you have several deleted answers you might get a temporary suspension. Just a little heads up! — Stewie Griffin 44 secs ago

8

Anonymous

9:22 AM

10/10 troll

5

Destructible Lemon

9:36 AM

Anyone else interested in the lojban lang site proposal?

it will be a cool site

Down Christopher

10:16 AM

@StewieGriffin 10/10 would roast again

New Main Posts

10:37 AM

0

Q: Is this even, or odd?

Note: There is not been a vanilla parity test challenge yet (There is a C/C++ one but that disallows the ability to use languages other than C(++), and other non-vanilla ones are mostly closed too), So I am posting one. Given a natural number, output its parity(i.e. if the number is odd or e...

code-golf

Destructible Lemon

10:53 AM

ummmmm TIL my ribcage is uneven. the ribs on the right protrude slightly further out then the left side...

wtf

One time I was actually worried about cancer

but it turns out that it was normal

Also it's vaguely unsettling that I only just noticed my ribcage was like this

Jan Dvorak

@betseg you probably shouldn't joke about things like these

Destructible Lemon

Actually it probably only happened recently, but still

Anonymous

→ 2 messages moved to Trash

Anonymous

@JanDvorak Agreed

Jan Dvorak

FTR: the message gathered five blue flags before they got invalidated

Destructible Lemon

11:02 AM

It's probably just an uneven growth spurt. But it kinda messes with the instinct of wanting things to be even

HamZa

@DestructibleLemon the body is hardly even imho

Jan Dvorak

It might be best to avoid using chat for medical advice altogether

Destructible Lemon

which is why I didn't ask for medical advice

Also it's only about a millimetre or two difference so it's kind of subtle

TuxCopter

11:19 AM

Hello!

PhiNotPi

11:37 AM

Hi

I'm thinking of writing a challenge to output "URA"s (uniformly redundant arrays) which are lists of 1s and 0s that have a "flat-tailed cyclic autocorrelation" which is easier to explain with an example than words:

 0  0  0  1  1  1  0  1  1  0  1

For any number x = 1...10, there exists several solutions to (a-b)%11 = x, but importantly the number of solutions is the same for every x.

This binary string can also be represented as the set {3,4,5,7,8,10}

x=1 -> (3,4) (4,5) (7,8)
x=2 -> (3,5) (5,7) (8,10)
x=3 -> (4,7) (5,8) (7,10)
and so on

it wraps around so x=4 -> (3,7) (4,8) (10,3)

user165474

12:13 PM

@PhiNotPi Wait, so what I don't get is what's the list of 1s and 0s used for?

PhiNotPi

Simple DAG answer-chaining concept: each new answer can chain off of multiple previous answers, with the restriction that the none of its ancestors can be ancestors of each other (so you can merge multiple branches together but can only chain once per branch). The functionality of the program has to build off of its ancestors... perhaps the functionality could be that it has to perform some kind of operation based on the structure of its family tree/web.

@HyperNeutrino The bits are another way to represent the numbers.

Also, any leading/trailing 0s are important since the length of the list is the divisor for the mod operation.

I don't think my answer-chaining concept would work as-is, because answer-chaining challenges need to be "self-limited" in some way, so that the chain will eventually be exhausted once there is no longer a way to extend it.

This might actually be interesting to do as part of a challenge where you are restricted by edit-distance. The controller should be able to automatically calculate edit distances and then automatically determine an answer's position in the DAG.

The scoring algorithm will end up being rather complicated.

Instead of measuring "depth" by an answer's distance to the root, it will be measured by distance to the oldest ancestor that it's the youngest descendant of. This way, people who make small side-chains to longer chains only get points according to the length of the sidechain itself, instead of getting a bonus due to the length of the main chain.

Or perhaps it is not worth scoring by depth at all... instead, just by how many parents the answer has.

With the controller set up so that your answer is automatically placed to have as few parents as possible (with the requirement that no other answer is a valid parent given the list of parents already assigned).

user165474

1:13 PM

@PhiNotPi Hm... I still don't think I get it. So like, given the binary string, we produce the set?

PhiNotPi

@HyperNeutrino you produce the list binary strings (or sets, same problem) that match the property

Alternative challenge would be to verify the property.

ais523

in challenges where you can brute-force generate, verify challenges are normally neater if there's no trick, generate challenges tend to have more scope for creative solutions but are less interesting if there isn't a creative solution

user165474

Okay, so are we given the modulus (in this case 11), or something else?

ais523

I think the modulus equals the length of the list

so generate = given modulus, find lists of that length with that property

PhiNotPi

yes

ais523

1:21 PM

verify = given list, see if it has the property with modulus equal to the length

PhiNotPi

I think I'll do the verify challenge because I think the generate challenge will just be brute force.

ais523

I think generate will probably be brute-force here too

(of course, in Prolog, the two are normally the same challenge...)

user165474

In your example, for x = 1, why is 5, 6 not a solution? Am I missing something?

ais523

because the sixth element of the list is 0

all the numbers in the pairs match 1s in the list

let me try my own attempt at stating the property:

find a set of integers, each in the range 0..(n-1) inclusive, so that if you take size-2 subsets of the set, and group them by the difference between their maximum and minimum, each of the groups will be the same size

(differences here wrap around mod n, and all possible differences other than 0 must be represented)

user165474

Oh okay. That makes sense. So the challenge is now to verify this property, not generate a set with this property, right?

ais523

1:28 PM

unless there's a trick to generation that's faster than brute force, verification is likely a better challenge

(also I didn't mean "maximum and minimum", but rather "the two elements")

New Sandboxed Posts

1

A: Sandbox for Proposed Challenges

The Tenacious Thai Calendar code-golf number-theory In the Thai calendar the year 2017 corresponds to 2560. The Thai calendar is always 543 years ahead of the Gregorian calendar. Observant coders will note that 2560 is equal to 2^9 * 5, in other words it has 10 prime factors. This will not ha...

Poke

1:46 PM

bleh, today is a code review day

i may not survive

user165474

1:57 PM

@Poke Good luck!

Poke

thanks :P

user165474

:P

fəˈnɛtɪk

2:46 PM

Should we put a snippet to view all the shortest answers by language for the even/odd challenge

fəˈnɛtɪk

3:19 PM

@Riker Assembly isn't 1 byte per character, it is x bytes per command. I'm not sure how much RET is though.

Riker

hm, true

edited it back to characters, thanks for the notice

AdmBorkBork

RE(k)T

Riker

lol I just made it in with the 5 min ninja edit time

New Meta Posts

0

Q: Can lambda parameter types be left off if potentially inferable from context?

This Java answer (and this one) uses a lambda that does not explicitly declare its parameter type, but this Scala answer includes a parameter type. in both cases, the type could be inferred when it is assigned to a variable. For example, for a lambda that takes an int and returns an int: Function

discussion policy code-golf

PhiNotPi

3:39 PM

@Lembik I've also been looking at symmetrical near-URA matrices (all without property X): gist.github.com/PhiNotPi/81130563a54cef45c45f30d076bf58f9

Down Christopher

I was taking a SOL today and... The SOL teacher person got mad at me like 3 times for dumb reasons

First time I had typed something in the username bar as I was bored

Second time I was using one of the tools included (it lets you block the screen out and only see one line of text

Third time I was using the tool and another lady came up and said that the other one (who was getting mad at me) said I was "Flashing the screen" and "Distracting others"... I was just working on my test and had nobody sitting by me...

If anybody saw my screen they were cheating so....

Nathan Merrill

3:53 PM

@MartinEnder what was your edit on my post?

fəˈnɛtɪk

he added a tag

Nathan Merrill

I don't really care, I'm just curious :)

I'm pretty sure I added the 3 tags on my challenge

fəˈnɛtɪk

He removed it during grace period

Nathan Merrill

oh, so he made an edit, then undid it?

Down Christopher

Guys I uhh made a bad idea

fəˈnɛtɪk

3:54 PM

You can check what edits were made by clicking on the edited by ... x min ago

Down Christopher

in Trash on Stack Overflow Chat, 4 mins ago, by Down Christopher

@Queen say a

Nathan Merrill

right

Down Christopher

Just look at my choices

You can see when I realized what I had done by my removed message

Nathan Merrill

I thought that "[Edit removed during grace period]" meant that it didn't show the edit because the post was still in the grace period

makes much more sense the other way :)

fəˈnɛtɪk

It shows edit removed during grace period

Martin Ender

3:56 PM

@NathanMerrill added classification but then saw that you can output on a spectrum, so I removed it again. although it might still be applicable because it's basically a classification with confidence information attached. wasn't sure though.

Nathan Merrill

I'm not sure its really a classification challenge. Like, you could argue that is "classifying games where white wins", but that feels rather different to "classifying types of flowers"

AdmBorkBork

@MartinEnder I was about to tag it the same, but was also hesitant...

Nathan Merrill

even if the output was binary, it still feels different

dunno

I'd be ok either way

AdmBorkBork

If the output was binary, it would be decision-problem

fəˈnɛtɪk

It should be tagged statistics

Martin Ender

3:59 PM

@NathanMerrill what is a classification if "here is some data, tell me into which of these two groups it belongs" isn't?

New Main Posts

5

Q: Chess Analysis with Limited Information

In this challenge, you are given a limited amount of information about a particular game of chess, and you need to predict who won the game. You are given two sets of data: Piece counts (What pieces are still alive) Board colors (The color of pieces on the board) More importantly, you don't...

code-challenge chess test-battery

Nathan Merrill

@MartinEnder From an input/output standpoint, it absolutely is. I personally think that the actual algorithms used are going to be different than standard classification problems

like, you're going to try and predict which pieces go where

fəˈnɛtɪk

I would argue that decision problems are a binary classification problem

Martin Ender

I feel like that's just applying domain knowledge to solve the classification problem, but it's a classification problem nevertheless.

Nathan Merrill

as opposed to simply having weights for each values and combinations of values

@MartinEnder and that very well may be true. I've only looked at classification problems from an educational standpoint, so I'm nowhere near an expert in them :)

so, I'd be ok with it tagged either way :)

New Sandboxed Posts

4:03 PM

0

A: Sandbox for Proposed Challenges

Try it online has a 60 second time out. You must make a program that is supported by TIO that takes no input and runs for 59 seconds and ends without error and produces any output. Your goal is to use the most CPU percent and have the closest time to timing out. Scoreing Percent CPU used - (60...

Kritixi Lithos

@fəˈnɛtɪk Yes

Anonymous

Classification to me seems to be more about classical logic - this element belongs to one or more of a set of sets. For fuzzier logic like the challenge in question (where a probability of the element being in one of two disjoint sets is computed via whatever black magic), classification doesn't seem appropriate to me.

AdmBorkBork

Hrm, that's a good distinction.

Martin Ender

Probabilistic classification

In machine learning, a probabilistic classifier is a classifier that is able to predict, given a sample input, a probability distribution over a set of classes, rather than only outputting the most likely class that the sample should belong to. Probabilistic classifiers provide classification with a degree of certainty, which can be useful in its own right, or when combining classifiers into ensembles. == Types of classification == Formally, an "ordinary" classifier is some rule, or function, that assigns to a sample x a class label ŷ: ...

I'd say classification with a confidence value is still classification.

Anonymous

Eh, fair point

AdmBorkBork

4:09 PM

@MartinEnder Right, but is that how we've used the tag here?

Martin Ender

I don't know, I don't think it's one of our very consistently used tags.

(which we could change...)

Nathan Merrill

The real question is "Are people interested in classification challenges going to be interested in the chess one?"'

AdmBorkBork

Consistently using tags? That's unpossible.

Mendeleev

CMC: display /proc/cpuinfo

Anonymous

But still, there seems to be a significant difference between how we've used the tag previously (as classical classification - which of these sets does this element belong to?) and the challenge in question (which is probablistic classification).

Nathan Merrill

4:11 PM

you know, since psychology is a well-defined field :)

Anonymous

We've used the classification tag as "given an input, output the set(s) that the input is a member of"

PhiNotPi

Are we trying to classify a type of classification?

AdmBorkBork

Classiception

Martin Ender

@NathanMerrill Yes, because outputting 0 or 1 for each test case is a viable strategy (and in fact is necessary to obtain the optimal score).

Anonymous

While it can certainly be argued that this challenge is also a classification challenge (because it uses probabilistic classification), the question is: are such types of challenges different enough from the typical usage of the tag to warrant not having the tag, or having a different tag?

Mendeleev

4:13 PM

Btw are CMCs on topic in TNB?

Anonymous

@Mendeleev Yes, but when there's a site-relevant discussion going on, it's best to not interrupt it with CMCs

Anonymous

Like now

Mendeleev

@Mego yeah I totally didn't see the discussion. I scrolled up and thought that the room was idle.

PhiNotPi

4

A: Sandbox for Proposed Challenges

Programming Puzzle or Code Golf? (A judging books by covers question) ^Might need a better title. code-challenge This question is based off the "Let's Judge Some Books By Their Covers" question. Browsing the site, I see that 1859 of our 2692 questions (69%) are tagged code-golf. My questi...

^ a classification challenge I'd like to post soon

Nathan Merrill

@Mego I mean, if a new tag would inspire new types of challenges like this one, then I'd be all for creating a probabilistic-classification

because we're already saturated with enough golfing challenges

Anonymous

4:18 PM

@NathanMerrill I'm going to vote that classification is good enough for now, but if more probabilistic classification challenges pop up, we can make the tag and apply it where relevant.

Martin Ender

4:30 PM

I knew Mathematica was bad at string manipulation but the fact that StringRepeat["x", 0] doesn't work because it expects the second argument to be positive is just ridiculous.

AdmBorkBork

@MartinEnder StringRepeat["x", +0]

Martin Ender

...

AdmBorkBork

Maybe it needs to be a signed zero.

mbomb007

HTTPS works on PPCG now, though there's no redirect yet

Kritixi Lithos

It always used to work

mbomb007

4:42 PM

No it didn't. SE only recently added https.

408

Q: Network-wide HTTPS: It's time

Update 2017-03-16 We've redirected all child meta traffic from meta.*.stackexchange.com to *.meta.stackexchange.com, and are now forcing HTTPS. We have also rebaked links inside the network (except comments) to point to the new domains and protocol. We'll get to comments at the end. We are awar...

discussion featured ssl announcements

Jan Dvorak

It sorta worked unofficially before it sorta worked officially. The only difference is a ton of automated edits (don't try this at home, but we can) and that you can file bugs now.

Nathan Merrill

hey, lets say you have a 2D grid, and you randomly fill some of the squares in. You need to represent the Xs in as few rectangles as possible

is there a name for this problem?

An example problem is:

OOOXXXX
OOXXXXX
OOXXXXX
OOOXXXX

Jan Dvorak

bounding box?

Nathan Merrill

you would need two rectangles to fill the Xs

one of them would be a 4x4 square

Jan Dvorak

Oh. Rectangle covering

Nathan Merrill

4:50 PM

the other would be the 2x1 rectangle

oooh, that's the term

thanks !

Jan Dvorak

` en.wikipedia.org/wiki/…

Geobits

Don't we have some sort of challenge about that? I know I've seen it somewhere on SE at any rate

Nathan Merrill

51

Q: Algorithm for finding the fewest rectangles to cover a set of rectangles without overlapping

I have a set of rectangles and I would like to "reduce" the set so I have the fewest number of rectangles to describe the same area as the original set. If possible, I would like it to also be fast, but I am more concerned with getting the number of rectangles as low as possible. I have an approa...

algorithm language-agnostic geometry rectangles

Martin Ender

21

Q: Cover a Region with Rectangles

Input Your input in this challenge is a list of integer pairs. They represent the southwest corners of unit squares on the plane, and the list represents their union as a subset of the plane. For example, the list [(0,0),(1,0),(0,1),(1,1),(2,1),(1,2),(2,2)] represents the red-colored set in t...

code-golf geometry grid

doesn't ask for an optimal cover though

Geobits

Oh, I've seen both of those posts and my brain merged them into one.

Nathan Merrill

4:53 PM

lol

Geobits

I think I was looking at the SO one while trying to dissect a map for pathfinding some years back

Григорий Перельман

Challenge idea: output 20^(5*6^69). Does not have to finish running in the lifespan of the universe, however it should never use more than a few gigabytes of memory, including the memory used to store the number itself. The idea is that you have to print out part of the number, and then forget about it as you calculate the next bit. Does that seem intresting? Similar to the infintely transmit pi problem.

DJMcMayhem

What's the significance of that number?

Григорий Перельман

The number is fairly arbitrary, the point is that it's huge. (It's the amount of agility that meepo would have if he had 6 aghanim's scepters and they stacked with themselves exponentially)

Kritixi Lithos

@ГригорийПерельман 79

Григорий Перельман

4:58 PM

Did... you interpret ^ as bitwise xor?

Geobits

Kritixi is a robot, so you have to be careful with syntax

Kritixi Lithos

@ГригорийПерельман Hehe, now where's my cookie?

@Geobits No, you're the robot

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