The Nineteenth Byte

12:00 AM

I got bored with the pattern matching language and started playing with new code for inca3. I've got some encouraging results in accessing the extended graphics characters with xterm. This should allow me to pack even more commands into a byte, at the expense of defining several more conversions (text-input format, disk-format, memory-format, text-output-format).

I also want to combine the ability to use longer names with the existing ability to use names without intervening spaces. I think I can do this by taking the set of decreasing prefixes of a string, returning the longest prefix that is defined and pushing back the remaining name fragments to the scanner.

Martin Büttner

12:13 AM

@Calvin'sHobbies only now did I realise the significance of the number 99 for your question today -.- (despite checking earlier whether question no. 100 would be your next)

PhiNotPi

I leave PPCG for a few hours and I come back to one of my posts being close-voted?

Martin Büttner

we do that all the time when you're not watching

New Sandboxed Posts

12:31 AM

0

A: Sandbox for Proposed Challenges

Challenge about seals stranded upon an iceberg (temporary title; title suggestions always appreciated!) code-golf A family of seals are stranded upon an iceberg in the Artic Circle. There is a radio transmitter located on the iceberg which the seals can use to call for help. However, only the ...

randomra

12:45 AM

^ The backstory made me laugh. :D

Doorknob

2:17 AM

The sandbox just got its 16th "More than 10 answers posted to this question in the past 7 days" auto-flag.

Yep, sixteen. I am slightly annoyed at this.

PhiNotPi

How often does it get an auto-flag?

Do a lot of PPCG questions get auto-flagged?

Doorknob

Every 7 days, I would assume.

Autoflags are about 80% of the flag workload here -_-

PhiNotPi

Well, it seems like the mods tools are simply making more work for themselves.

At that point, they're not really "tools."

Doorknob

Heh, occasionally they're useful. But usually it's just "oh, hey look, another 'too many edits' autoflag! declined"

PhiNotPi

On the website I "moderate", there's a flagging system, but all it does is send an email notification to the mods' (special purpose) email addresses.

I'm just listening to some music right now.

Waiting on some interesting KOTH entries to show up.

randomra

2:46 AM

I'm thinking of a challenge where everyone's name would be hashed to like 3 Turing-complete language on esolangs.org and you should have to do the given task in one of those languages.

Doorknob

That would be... interesting.

randomra

It's hard to find the interesting ones in esolangs and here the good ones could be voted to top.

Doorknob

Or there could be a challenge to stick in your username/userid and have the program spit out a deterministically random esolang (possibly making it change every day?), and the submissions to that challenge could then be used by users here who want to try new languages.

randomra

Yeah, mine would have a snippet with name input, language links output too.

might worth to add the daily change too

But in your proposal you don't get to vote so you never know which is a good language.

Doorknob

And it would be really disappointing to get a language like this one. :P

randomra

2:55 AM

I would restrict it to the Turing-complete ones: esolangs.org/wiki/Category:Turing_complete

Doorknob

Oh, whoops, right. I was looking at the "all languages" list.

New Sandboxed Posts

5:09 AM

0

A: Sandbox for Proposed Challenges

Crack a Keyed Caesar Cipher Given the input below, write an algorithm to crack a keyed Caesar cipher. A keyed Caesar cipher consists of a word which acts as a key (eg puzzle) the rest of the alphabet is then shifted as demonstrated below: a b c d e f g h i j k l m n o p q r s t u v w x y z ...

Optimizer

6:44 AM

@Calvin'sHobbies like I was not right :P

Calvin's Hobbies

7:46 AM

Is there a main meta post that talks about not using languages invented after the challenge? I can't seem to find one.

Sp3000

Interesting... I'm having trouble too

Calvin's Hobbies

Is it just an unwritten rule? :P

Sp3000

Well it is written... just all over the main site itself

Maybe this post?

Closest I could find

Optimizer

8:05 AM

@Calvin'sHobbies kind of

New Meta Posts

8:26 AM

0

Q: Can I ever answer with a language invented after the challenge was posted?

A common rule here on PPCG is that programming languages invented after a challenge was posted cannot be used to answer that challenge. (I've had trouble finding a specific meta post that addresses this though.) This rule makes total sense because without it, someone could "invent" a language th...

Optimizer

@Calvin'sHobbies dude

I asked the same question like 1 minute from you

:/

Calvin's Hobbies

Hahaha, too slow! Sorry ;)

Optimizer

:D

you should change the last few lines of your question

remove themm

they should be answers.

New Meta Posts

Recent Questions - Programming Puzzles & Code G…: Should answers with languages/versions newer than the question be considered non competing answers?

posted on March 10, 2015 by Optimizer

It has considered as an unwritten rule for a long time now. Lets have a written decision on this. This post targets all answers written in languages or versions of languages which were created/launched after the question was asked. Whether the newer language/version was influenced by the question or not, we should have a single stand.

Optimizer

wow ^ what a bug!

I have deleted the question long since. its not even a proper one box

Martin Büttner

8:57 AM

@Calvin'sHobbies there's this meta.codegolf.stackexchange.com/a/1420/8478

@PeterTaylor Do you happen to know the computational power of a Turing machine that can only perform an arbitrary but finite number of steps?

Peter Taylor

10:50 AM

@MartinBüttner I'm not quite sure what you mean.

PhiNotPi

11:06 AM

I think he;s asking the time-version of "what's the computational power of a Turing machine with a finite memory"

Kinda like how a real-world computer can have almost an arbitrarily large memory, but never "enough" (infinite).

@PeterTaylor ^ ping :)

Zgarb

11:22 AM

I interpret it as "describe the class of those Turing machines that always halt".

randomra

12:14 PM

Just to add my thought: for me the "arbitrary large but finite number of steps" seems to be the definition of "infinite steps".

PhiNotPi

12:25 PM

Maybe this wiki article is relevant: Machine that always halts

Martin Büttner

12:58 PM

@Zgarb yes, although I think that should be equivalent to machines with finite memory, since you can solve the halting problem for those.

@PhiNotPi thanks that's what I was looking for

Zgarb

@MartinBüttner What do you mean by finite memory? Is it constant, or given by some computable function of input size (then it's not equivalent to the above)? Or is it given by some uncomputable function of the input size (then their halting problem is probably not solvable)?

Martin Büttner

yeah actually I think that total Turing machines might be more powerful that what I'm looking for

there will be an a priori limit to the number of steps the TM can take. that limit can be set arbitrarily (and can probably be at least a linear function of the input size, possibly even polynomial), but it will be bounded.

okay, the limit can definitely depend on the input size by a computable function, but probably not by any computable function.

Zgarb

Well, then you just get all functions in the respective time complexity class.

Martin Büttner

right, that makes sense

@Rainbolt you ninja-deleted your comment while I was replying :D

out of curiosity, did you get a ping anyway?

Rainbolt

I deleted it within ten seconds of posting, and no.

I know why you replied without even reading

Martin Büttner

1:10 PM

heh

Rainbolt

That post is very pedantic

what, my comment?

The OP

oh okay

"I know I can't win with an answer written in a language that was invented after the challenge, but can I technically post my answer anyway and just not win?"

Answer is: who cares really

Martin Büttner

1:13 PM

people who want to answer old challenges and are afraid of down and delete votes for posting a technically invalid answer?

@Zgarb that is a really interesting challenge

Rainbolt

@MartinBüttner This guy was't afraid - codegolf.stackexchange.com/a/32869/18487

Anyway it's been asked and now it'll have an official answer

Martin Büttner

I for one would like the disclaimer I suggested in the comment to be made mandatory for such answers

Zgarb

@MartinBüttner I started thinking about the reverse operation of merging one day, and was surprised that it is not trivial whether it can be done for a given list, but it admits a short algorithm (at least if you have no duplicates).

I don't know how much harder it is with duplicates. Depends on the tie-breaking rule, I guess.

luser droog

I've been playing more with the xterm graphics charset. I've cobbled together an alternate keyboard which you can switch to/from with ctrl-N and ctrl-O.

Optimizer

3

A: Spiral Programming

Python 2, 290 It's probably really bad, but I tried :D The output contains trailing spaces, but that is not forbidden in the spec. m=x=y=c=0 l,f=1,[31*[' ']for t in[0]*31] for i in[0]*input(): k=m%4 f[14+y+(2<m<6)][14+x-(m>3)],x,y,c='|/_\\'[k],x+(k>0)*(2*(4>m)-1),y+(k!=2)*(2*(2<m<6)-1),c+1 ...

luser droog

1:23 PM

The layout is not final. I just quickly defined everything so I could display it.

This does tie it to xterm or other vt220 terminal emulators.

so a windows port will be a chore.

Wondering if I can cut/paste these characters from the terminal. Do they translate?

◆1234567890-=
QWERTYUIOPπ£≠
␊⎼␋⎺⎻[]\
ASDFGHJKL:"
⎽␍°±␤;'
ZXCVBNM<>?
␌␉,./

Hm. kinda.

Martin Büttner

1:51 PM

@Zgarb I guess then I need to figure out what exactly sort of functions I can exactly compute for the time limit

-exactly

PhiNotPi

2:11 PM

Running a Core War battle now.

It's pretty slow.

Well, I would expect that, considering how many battles are being played.

About 16000 per pair.

Dwarf beats Imp

It will probably be worth my time to optimize the controller.

Unofficial Leaderboard:

5 - CopyPasta
3 - Janitor
2 - Dwarf
2 - Imp

I'm going to ditch some debug text and see if I can run an actual full tournament his time.

Because I think the fact that debug text was generated each cycle (regardless of whether it will be printed) would slow it down a lot.

The above board was done with a small core size.

In the worst case, both opponents would be imps that can't win.

Then the full war between those two would be (8191 possible starting offsets) * (8 * 8192 max time per battle) * (2 options for who moves first each battle) = 1.07 billion ply (total instructions executed during the war)

It's about seven minutes per pair-off right now.

PhiNotPi

2:43 PM

Official pairwise results, hot off the press!

Dwarf Imp

CopyPasta = Imp

Janitor = Imp

CopyPasta Dwarf

Janitor Dwarf

Rainbolt

All of my databases have entered the "Emergency" state. That sounds bad

On the bright side, I have two million READONLY rows.

PhiNotPi

Janitor CopyPasta

Leaderboard:
    5 - Janitor
    3 - CopyPasta
    2 - Dwarf
    2 - Imp

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