The Nineteenth Byte

4:37 AM

@NewMainPosts Oh, I guess I have a close-vote hammer. Next time perhaps I'll be a bit more careful and wait for more closevotes

New Main Posts

5:55 AM

0

Q: Solving the rose garden view point problem

In Ooty, India there is a huge rose garden. There are 4000 rose species there. Since there are so many species, authorities decided to make some view points to enjoy views. Now from 1 view point one can see only few species on roses. If they want to see more species then they have to switch view ...

New Meta Posts

7:39 AM

0

Q: List of Invented Languages

A great problem on PPCG is people posting an answer in Pyth on an old question (presumably trying to get the excavator badge) but being shot down because their language was created after the question was posted. For this reason, we need a list of languages invented by PPCG users with their creati...

discussion

New Main Posts

2:58 PM

1

Q: Staircase writing

Write a program or a function that will output a given string in a staircase fashion, writing each part of a word that starts with a vowel one line below the previous part. For example: Input: Programming Puzzles and Code Gold Output: Pr P C G ogr uzzl ...

code-golf string

Martin Büttner

3:48 PM

quite the party in here

Dennis

Parteh!

Martin Büttner

@Dennis your CJam answer is taking quite long ;)

yay, I made it onto Gems from SE :D

4

gemsfromstackexchange.tumblr.com/post/122940343706/…

Geobits

That page has 'next' on the left and 'previous' on the right. It's downright anarchy.

Dennis

4:08 PM

@MartinBüttner Was a bit busy. :P I stumbled upon your telescopic challenge last night. I think the way the accepted answer implemented its idea completely derailed the associated meta discussion.

That challenge is solvable in 17 bytes btw, using CJam.

Martin Büttner

yeah, that's true

@Dennis post that then ;)

Dennis

4:30 PM

Done.

Sp3000

4:54 PM

@MartinBüttner Who runs that tumblr D:

"Posted by Alex" hmm wonder which Alex

Optimizer

Alex A, or Alex B ?

Sp3000

Note to self: If I ever write a staircase challenge, ban control chars

Dennis

@MartinBüttner Well, here it is, but it looks like I won't be able to beat Retina.

Alex A.

@Sp3000 It was me Alex!

@Optimizer ^

Dennis

Why is there a Cursor Horizontal Absolute, but no Cursor Vertical Absolute sequence? :/

Alex A.

5:04 PM

@Dennis The universe is a cruel, cruel place.

Dennis

@Sp3000 No exceptions? I'd like to use linefeeds. :P

Sp3000

Ahaha nice, I was wondering if it was one of those people-post-stuff tumblrs or whether it was run by one person

Alex A.

Anybody can submit but it needs to be approved, idk by whom.

Sp3000

@Dennis We need a name for "printable ASCII + tab + CR + LF" so we can call it something simple all the time

Dennis

@Sp3000 I'm not sure sure I'd want tab and CR by default either. CR may be required for Windows, but it's just as cheaty on *nix.

Sp3000

5:08 PM

I'd be fine dropping CR, but what's wrong with tab?

Alex A.

The first time I saw "*nix", I thought it was a typo. :/

Optimizer

no, its a Pokemon

Alex A.

Haha really?

Dennis

@Sp3000 Depends on how it's used. If the question call for tabs, fine, but using them to replace spaces...

Lembik

@MitchSchwartz I have realised who we need for my challenges now... facebook.com/GennadyKorotkevich?fref=ts :)

Dennis

5:15 PM

In the output, that is. Tabs in source code are fine, obviously.

Lembik

@MitchSchwartz or petr-mitrichev.blogspot.com :)

Alex A.

@Lembik Or even this guy.

New Main Posts

2

Q: The GOLF CPU Golfing Challenge: Prime Partitions

This challenge is the first of a series of fastest-code problems that should be written in the GOLF CPU. A partition of a number, N, is a list of numbers that add up to N. A prime partition is a list of prime numbers that add up to N. For this challenge, you are given a single integer N. You ...

fastest-code golf-cpu

Optimizer

That moment when you stay in the 19K for the longest time ever..

trichoplax

5:30 PM

Request for obvious holes:

0

A: Sandbox for Proposed Challenges

Uniquely separated pixels code-challenge Graphical intro This is not a graphical challenge (the input and output are composed of integers), but I'll take a graphical approach to the question: For an N by N image, find a set of pixels such that no separation distance is present more than onc...

Lembik

@AlexA. is he famously good at coding? :)

Alex A.

@Lembik I actually have no idea who that is.

Lembik

@AlexA. en.wikipedia.org/wiki/… this person

Alex A.

1699-1753... pretty sure he was good at GolfScript.

Lembik

that sounds plausible

Alex A.

5:39 PM

If he had lived any longer he clearly would have adopted CJam.

Lembik

@AlexA. you know my suggestions were real living people don't you? :)

Alex A.

Of course :P

My suggestion was a real living person.

Lembik

I feel the reward for winning topcoder should be a day on PPCG :)

Alex A.

What's topcoder?

Lembik

seriously?

Alex A.

5:41 PM

For realsies.

Lembik

you didn't click on any of my links!

TopCoder

TopCoder is a company which administers contests in computer programming. TopCoder hosts fortnightly online competitive programming competitions—known as SRMs or "single round matches"—as well as weekly competitions in design and development. The work in design and development produces useful software which is licensed for profit by TopCoder. Competitors involved in the creation of these components are paid royalties based on these sales. The software resulting from algorithm competitions—and the less-frequent marathon matches—is not usually directly useful, but sponsor companies sometimes provide...

Alex A.

Oh interesting

I clicked on that link

But not the others

I am BottomCoder.

Lembik

that doesn't sound good!

Sp3000

Oh, when did they update the site?

Lembik

hi @Sp3000

Sp3000

5:47 PM

Hi Lembik

Martin Büttner

@Dennis yay :)

Dennis

I figured you wouldn't be losing any sleep over this. :P

Martin Büttner

@Optimizer are you doing a Howard? :)

Optimizer

F u. not gonna last that long! :P

Dennis

That whole if-we-moved-n-times-down-we-have-to-move-n-times-up business just doesn't agree with CJam.

Optimizer

5:59 PM

Try space padding ?

Dennis

@Optimizer If I transpose, I'd have to pad in both directions. Worth a shot, but probably longer.

Optimizer

try to use .*

I mean \.?

Dennis

Is .? a thing?

Optimizer

its a regex. duh!

Dennis

Was thinking about CJam operators. :P

Optimizer

6:08 PM

that is why I put a \

Dennis

@MartinBüttner Your staircase answer still says Bash.

Martin Büttner

oh, thanks

Eric Tressler

6:58 PM

Hallo

Martin Büttner

long time no... read?

Rainbolt

Chat.... long time no chat

That's like you walking up to someone and saying "Long time no listen."

2

Eric Tressler

well, here I am

I have taken off work today because my head feels like it is going to explode

trichoplax

Welcome back

Eric Tressler

what's new?

trichoplax

7:03 PM

Thankfully people in here never say things that would make your head explode

Rainbolt

I could probably make your head explode

Eric Tressler

oh man. after it explodes once, I fear it'll be hard to tell the second time

And, incidentally, I would like to thank the NSA for being thoughtful moderators of this chat

they never really ask for anything, those guys

what's new?

Geobits

They don't ask, but they receive enough.

trichoplax

I can't think of anything fundamentally new

I've actually started posting questions, with hilarious results due to lack of foresight.

Eric Tressler

Hubris is the best medicine

trichoplax

7:08 PM

We have Stack Snippets KotHs now, that's kind of new

Eric Tressler

what's that

trichoplax

It started with this

You can watch it play direct from the question, which is nice, but it does mean javascript only

Eric Tressler

i wish i had seen that while it was live

i've been fucking with JS a lot lately

mostly trying to cheat by using the GPU to calculate stuff it isn't intended for

trichoplax

I'm planning at least one more myself

After 4 months in the sandbox with 1 upvote and 1 downvote, should I just go ahead and post and see what happens?

0

A: Sandbox for Proposed Challenges

Uniquely separated pixels code-challenge Graphical intro This is not a graphical challenge (the input and output are composed of integers), but I'll take a graphical approach to the question: For an N by N image, find a set of pixels such that no separation distance is present more than onc...

Optimizer

thats not long enough.. leave it there for another couple

Eric Tressler

7:15 PM

To be more accurate, you should ingest 1 lb of sand and expel 1lb of sand and record your thoughts

trichoplax

@EricTressler Surely if it works it works

Eric Tressler

@trichoplax yeah, but it's weird to misappropriate shaders to do the dirty work

trichoplax

@Optimizer Thanks you always have the answers

Optimizer

@trichoplax not for this one.. sorry.. won't be posting ..

trichoplax

@Optimizer Whether anyone answers is my secondary concern. My primary concern is "is there an obvious optimal solution I've overlooked?"

Geobits

7:19 PM

I don't think there's an obvious optimal solution, at leats for my definition of obvious. I'm fairly certain you pulled 619 out of nowhere, though ;)

Eric Tressler

@trichoplax are you asking about your bot on that challenge?

trichoplax

@EricTressler no the sandbox post - is it a question ready to post to main

@Geobits 619 certainly isn't based on any estimates of solvability - it's the highest prime that still allows posting an image into a SE post without downsizing and losing the pixels...

And making it prime is a wild guess too

Geobits

Ah, then not out of nowhere. That satisfies my minor OCD tendency.

I'm sure it's large enough, though.

trichoplax

lol - happy to oblige

Eric Tressler

I don't really get your spec on first read

trichoplax

7:22 PM

As long as it's not too small, if it's too large for some approaches then at least everyone is restricted to the same approaches and can't find the best answer any time soon

@EricTressler Excellent. What needs to be clarified?

(I don't mean excellent that it's unclear, I mean excellent that I'm finding out before posting to main)

Eric Tressler

what do you mean by separation distance

trichoplax

Euclidean distance between the two pixels

Eric Tressler

are you aware of the math behind this problem?

trichoplax

Would it be better to say "find a set of pixels that have unique separation distances"?

Geobits

I wouldn't worry about it being too small. It looks like the 1D 'ruler' case still hasn't been solved (or at least proven optimal) for 619, much less bringing it to 2D.

Eric Tressler

7:25 PM

in general, all of the exploration here is open

trichoplax

@EricTressler I'm aware that research has been done in 1 dimension, and in 2 dimensions with vectors rather than scalars (which is more forgiving, allowing more points). I don't pretend to understand anything though

Eric Tressler

so I think it's not a good candidate for a problem

I think you should scrap the idea for now, and do something else

trichoplax

I was hoping for brute force random early entries, followed by gradual improvements as new answers arrive with tricks for cutting down the search space and avoiding wasting time

Eric Tressler

i've tried that; nobody responded to mine

trichoplax

Which was yours?

Eric Tressler

7:27 PM

oh god. i'll have to dig it up

17

Q: Horror Movie Search Party

Plot: Jimmy is missing; we have to find him. We should split up. Plot twist: Jimmy is already dead. But, our cast doesn't know that, so they need to search the whole area anyway. There is an N columns x M rows (1<=M,N<=256) grid of cells, either marked as "S" for the starting point, "." for op...

code-challenge graphs path-finding

trichoplax

Ah I remember. Only 1 answer. I wonder if a bounty would make a difference?

Martin Büttner

@trichoplax I bountied it

trichoplax

For my question I'm imagining some strategies that try to choose the best new place for a pixel while building up a solution from nothing, and others that randomly remove a pixel and see what else can be added instead.

Eric Tressler

and i just accepted your answer

Martin Büttner

oh, thanks :D

Eric Tressler

7:32 PM

@trichoplax can you link to your question

@MartinBüttner I had hoped other people would try it out. It's an interesting question IMO, but I guess it has too many parameters

trichoplax

@EricTressler I still mean my sandbox post

Martin Büttner

@EricTressler I thought it was a really interesting challenge.

I'm still interesting in doing a cartography KotH

Eric Tressler

@trichoplax have you run this through a SAT solver?

@MartinBüttner what do you mean? A level-set viewer, or something?

trichoplax

@EricTressler I haven't

Eric Tressler

I think you can translate it into SAT

New Sandboxed Posts

7:38 PM

0

A: Sandbox for Proposed Challenges

Print an ascii spiral in O(1) memory You may write a program or function that receives an odd, positive integer n as either an argument, or on STDIN (or equivalent for your system), and prints an ASCII spiral like so Input: 11 Output: *********** * ********* * * * * * ***** *...

trichoplax

Is that a reason not to post it, or a reason to expect at least one answer?

Martin Büttner

@EricTressler I don't know what a level-set viewer is. I'm thinking everyone has a flock of bots with limited field of view (similar to your challenge) and can move around some sort of terrain. At the end of the game, each player submits a map of the terrain. The one that has most cells correct wins.

durron597

@NewSandboxedPosts I'm trying to decide whether to restrict it to O(1) memory or O(n) memory. Specifically I want to ban O(n^2) to prevent people from drawing the spiral in an array, then dumping the array. Looking for feedback.

trichoplax

@EricTressler A formula with 619*619 conditions, or am I overcomplicating it?

Martin Büttner

I'm thinking about two features to make this interesting: a) "terraforming" (like redirecting rivers) to invalidate others' maps and b) having a sort of "base camp" which all communication must go through.

trichoplax

7:41 PM

@durron597 Would O(1) require hardcoding the maximum size spiral and then printing a section of it? I'm not sure even that would count though.

durron597

@trichoplax I think O(n) is probably okay.

trichoplax

Oh memory - ignore me

durron597

Yeah, memory.

Eric Tressler

pardon me, but I have a terrible headache; I'll come back to chat later today, or tomorrow.

durron597

I think drawing a spiral is super trivial in most languages that support arrays if you're allowed O(n^2)

trichoplax

7:43 PM

@EricTressler Hope you feel better soon

Eric Tressler

thanks. It's okay, I just don't want to read anything at the moment. 'later

Geobits

What exactly is n? Just the length of the top/bottom sides? I thought at first it was the number of segments, but there's 12.

Martin Büttner

@durron597 you might want to add some words that explain how the 11 relates to the size

durron597

I want to prevent that easy solution of filling out an array and then dumping it. Plus, without the restriction it's basically a duplicate of codegolf.stackexchange.com/questions/47578/spiral-programming

Martin Büttner

ninja'd

Geobits

7:44 PM

:D

durron597

The top of the spiral is 11 * long

Yeah, I'll clean up the language before it goes live. I'm really here asking about whether the restriction should be O(n) or O(1) memory.

Martin Büttner

O(n) sounds sufficient

Geobits

I'm not sure I understand the memory restriction anyway. Is there that big a difference between dumping it into an array and printing it one by one?

Martin Büttner

I predict answers based on ANSI escape characters (in either case)

@Geobits without the memory restriction, I'd generate the spiral along the spiral, but that (naively) needs O(n^2)

the next best thing is probably generating a sparse representation of the spiral

if you don't want that, you'll need O(1)

durron597

@MartinBüttner Yes, exactly.

Martin Büttner

7:47 PM

or O(log n)

durron597

What do you mean by sparse representation?

Martin Büttner

@durron597 store the positions of the * in a hash or so... then print the rectangle with space if the coordinates aren't in the hash, or with * otherwise

Geobits

Right, that's why I don't do [ascii-art], got it.

Martin Büttner

but in any case, I'd probably just move the terminal cursor around the spiral manually

durron597

@MartinBüttner Meh. Tracing the spiral is exactly what I was trying to avoid with the memory restriction

I suppose most common languages here support manipulating the terminal (as opposed to a sequential terminal?)

Martin Büttner

7:50 PM

then you need to disallow any control characters other than <LF> and <CR> and you need to do O(1)

@durron597 it's not a matter of the language... you just need to output some escape characters like 0x1B (see my answer for Staircase Writing from earlier today)

durron597

Oh, by sparse representation you meant basically using compressed memory somehow

@MartinBüttner How's that edit?

Martin Büttner

looks better, although I don't like the restrictive input format

what's wrong with command line argument or function argument?

durron597

@MartinBüttner That's not intentional. Let me try to find the meta post for standard language about that... unless you have it handy?

How's:

> function argument, command line arguments, or on STDIN (or equivalent for your system)

New Main Posts

0

Q: High Precision Metallic Means

Background The metallic means, starting with the famous golden mean, are defined for every natural number (positive integer), and each one is an irrational constant (it has an infinite non-recurring decimal expansion). For a natural number , the metallic mean is the root of a quadratic equatio...

code-golf

New Sandboxed Posts

0

A: Sandbox for Proposed Challenges

Gimme your best shot code-golf internet Introduction You're fed up. You've tried to sell your car but failed, not knowing whether your price is too high, too low or people are just too picky. Then a programmer decides to take a look at your car and makes you an offer using a program that he ha...

Martin Büttner

8:10 PM

@durron597 sorry, I left the PC. I tend to use a very similar wording

durron597

@MartinBüttner I posted it. Thanks for your help.

New Main Posts

1

Q: Print an ascii spiral in O(1) memory

You may write a program or function that receives an odd, positive integer n as either a function argument, command line arguments, or on STDIN (or equivalent for your system), and prints to STDOUT (or system equivalent) an ASCII spiral that spins inward clockwise where the top edge is exactly n ...

code-golf ascii-art string

Geobits

25 minutes in the sandbox. That might be a record, not sure...

durron597

@Geobits I didn't wait for 3 upvotes ;)

Mitch Schwartz

@Lembik had you not heard of tourist and petr until recently?

Dennis

8:19 PM

@MartinBüttner You can save a couple of bytes by replacing \e[B with \v (0x0b).

Martin Büttner

oh, I didn't know that a vertical tab is a single line

Dennis

The name suggests otherwise, yes.

New Main Posts

0

Q: Uniquely separated pixels

Graphical intro This is not a graphical challenge (the input and output are composed of integers), but I'll take a graphical approach to the question: For an N by N image, find a set of pixels such that no separation distance is present more than once. That is, if two pixels are separated by a ...

code-challenge

Martin Büttner

@Dennis thanks, edited

durron597

@xnor argh. do you agree that this is the best way to capture my intent

xnor

8:29 PM

@durron597 I believe so

so people can take in the input and store, for example, the current coordinate

durron597

Once you pointed out that capping n means that you can just have an array that is the maximum size it could be, I had to remove the cap.

With no cap means minimum O(log n) just to store the input, so... it has to be O(log n)

Lembik

8:51 PM

@MitchSchwartz No I am totally out of touch :)

@MitchSchwartz but I feel we should invite them over!

Mitch Schwartz

9:15 PM

they seem pretty busy as it is :)

Dennis

9:41 PM

@MartinBüttner Found a 30 byte Perl solution.

31 bytes. Can't get used to y being a vowel...

Sp3000

10:30 PM

vv Incoming question looks perfect for CJam's RLE, but I'm not sure if it's a dupe

New Main Posts

1

Q: Write a program that finds the most occurring paired letter in a string

The program must output the letter that is paired the most. For example, if your program was given the following string: "Sally's friend Bobby searched for seashells." it must output L because "ll" occurs twice, which is more frequent than the other pair "bb". Rules: Count if more than one...

code-golf string counting

Dennis

Is anybody working on the metallic means in CJam?

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