The Nineteenth Byte

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18:06

0

I'm surprised this hasn't been done before. If it has, (a) Sorry. (b) It's a good thing to re-ignite the game! Input: a/b Output: c/d where c/d is the reduced form of a/b Rules Must be a full program, not just a function. Shortest answer in bytes wins. Whole number results may include t...

code-golf

Gabriel Benamy

"I'm surprised this hasn't been done before" [closed as duplicate]

11

Dada

huhu, made me laugh @GabrielBenamy

Pietu1998

> It's a good thing to re-ignite the game.

sigh

Meanwhile, rate my Python pastebin.com/raw/E4deD47W

trichoplax

I was going to say Code Review it, then I saw it...

Pietu1998

18:23

That's Hello World if you're interested

trichoplax

@Pietu1998 I'm glad you told me - that was going to take me forever...

Pietu1998

Figured out a way to make really messed up Python code

9

Yodle

@TimmyD I'm below 200 again in my C# answer, but I'm not entirely sure I can leave the System.Func<string,int[]> definition for the inner lambda out of the count.

xnor

@Pietu1998 how does this work?

Pietu1998

@xnor do you know how decorators work internally?

xnor

18:28

i thought they are functions that act on the function in sequence, but these don't look like higher-order functions

so i guess not

Pietu1998

basically, a decorator is something that takes a function as argument and returns another "decorated" one. they just don't check that you actually return a function, meaning that e.g. using str as a decorator gets you "<function f at 0x12345678>"

xnor

oh, i see, all the functions are immediately passed to bool

New Main Posts

0

Q: Helicopter challenge

There is a helicopter flying 500 meters from the ground. It can fly up 100 meters, which takes 1 second. Or if it doesn't fly up it will fall 200 meters, which also takes a second. Build a program that takes input telling you to fly. When the helicopter falls it should output the time counter. I...

code-golf number

Pietu1998

most of them yes

it can also use stuff like len(str(function)) to get 26

xnor

that's funny

and the decorating happens when the function is defined, so the code is executed without the function being called?

Pietu1998

18:32

and of course you can chain the decorators, so @len\n@str\ndef f(): pass makes f == 26

@xnor exactly, the functions are just dummies

you could put anything inside with no side effects, since the function objects get discarded

(except for default arguments which would be evaluated)

xnor

this makes me wonder if decorating has any golfing uses, but i can't think of any built-in higher-order functions usable in golfing

if there were a function-composition function ...

Pietu1998

that might be cool

xnor

a lot of times you want to recurse on the input, but it requires some preprocessing, like converting a string to a number

Pietu1998

that specific case shouldn't be a problem since int(k) == k for any int k, but I think I get your point

xnor

you're right, that's a bad example

Pietu1998

18:37

but splitting a string might a good example

Anonymous

@Pietu1998 You're a mad genius

xnor

@Pietu1998 apparently it doesn't even work: the recursive call invokes the decorated function as well

Anonymous

Please add a shebang to the decoratorator script for great good

xnor

darn, the decorator actually requires a def to work?

it seems to not work on a lambda or a named function or built-in

feersum

Aww, you can't self-decorate a function.

Pietu1998

18:42

@xnor when you decorate a function, you replace the thing you assign to the variable altogether. if you find another way to do that it might work

@xnor def or class. would've loved it on other stuff too

@Mego effort

Anonymous

@feersum Well no, because the symbol hasn't been defined yet

Anonymous

@Pietu1998 It's so little effort that even the lazy goat would do it

Anonymous

#!/usr/bin/env python3

feersum

@Mego It could conceivably have been implemented in a way that you can.

def g(): ..... g = g(g)

xnor

recursive functions also have the property that the symbol is not yet defined, right?

Anonymous

18:44

@feersum Well your first problem is that you're trying to call a zero-argument function with an argument

feersum

@xnor The name lookup is done at execution time.

@Mego Don't take the example too literally.

Anonymous

Then provide a useful example :)

Pietu1998

@feersum This would work if g was unary though

feersum

It doesn't matter what the arguments of g are, because it gets an undefined name error before it gets to that point.

@Pietu1998 No it wouldn't.

I mean, it wouldn't work as a decorator.

Pietu1998

@feersum Well, this is true

Function variables only exist after being defined. They're not defined until the decoration is done

Anonymous

18:46

>>> def g(x):pass
...
>>> @g
... def g(x):pass
...
>>>

Anonymous

I don't see the issue

feersum

Haha. The "issue" is that you had to write the definition of g twice.

Anonymous

Unless you're trying to use something before you've even told Python what it is

Anonymous

Trying to call a function before defining it is never going to work

BlueEyedBeast

If you were in bytecode you could duplicate the function before decorating and assigning it a global

Pietu1998

18:48

@BlueEyedBeast Imagine decompiling this

BlueEyedBeast

I don't think it would be too bad

Anonymous

Sure, it might work in bytecode, but not in Python

Pietu1998

Or well, it might just be def g(x):pass\ng=g(g)

I bet decorators also get decompiled like that

Anonymous

You cannot use something before you define what it is. It's impossible. Thinking otherwise is a major logical flaw.

Pietu1998

(Or with a temporary variable)

@Mego Recursion is recursion

Anonymous

18:50

@Pietu1998 1) That's tautology. 2) What?

Pietu1998

You can define recursion recursively

Anonymous

You mean like def g():g()? That's because you don't actually try to call something before it is defined. At the point of definition, there are 0 calls to g(), and there will not be any calls to g() unless you call it elsewhere.

Nathan Merrill

the definition of a recursive function still occurs before the use of the recursion

right

Pietu1998

In the dictionary you write recursion: see recursion. Stack overflow is when you've checked where recursion is enough times and forget what you were doing

Nathan Merrill

even mathematically, you define f(n) = f(n) -1. f(n) is defined first

BlueEyedBeast

18:53

f(f(n)) = f(n)?

Pietu1998

@NathanMerrill f(n) is not defined first, but some special case such as f(0) is

Anonymous

Recursion doesn't require base cases. It's just a good idea to include them, or else you get stuck in an infinite hole.

Nathan Merrill

that may be true, but doesn't have to

f(n) = -f(n)

Pietu1998

therefore f(n) = 0 for all n

Anonymous

Or f(n) = ∞ on the projectively extended real line

TimmyD

19:07

For chess geeks, The Lone King puzzle over on Puzzling is really awesome.

2

DrMcMoylex

Yeah, I saw that. It looks awesome

TimmyD

Ooo, we're closing in on 100,000 submissions (questions and answers) total.

trichoplax

I love the step by step demonstration

Gabriel Benamy

Programming challenge: extrapolate the date and time of the 100,000th submission.

TimmyD

Are we starting a pool? Put me down for ~16 hours from now.

Kritixi Lithos

19:17

@TimmyD How do you see the number of submissions?

Gabriel Benamy

post number

Geobits

@TimmyD 14 hours, so 2016-11-16 0918 UTC

Gabriel Benamy

I love how sometimes, brainfuck answers get more upvotes than Jelly answers

BlueEyedBeast

@GabrielBenamy why is that surprising?

Gabriel Benamy

It's just amusing, because they're usually several hundred times the length

TimmyD

19:23

@Geobits I may have just doomed myself, since I just posted a challenge which means the submission count is going to go up.

Geobits

Hmm. Only 43 to go. I think 14 hours might be too far out too :(

Kritixi Lithos

Submission 1337

New Main Posts

0

Q: Create Fluffy Blocks

(randomly inspired by this question) Let's make a drawing from some pipes | and hyphens -. If we pick a subset, you can see it forms a rectangular box or block shape (meaning that the corners are formed by |- or -|). For this challenge, we're concerned only with the corners - the vertical and ho...

code-golf ascii-art

BlueEyedBeast

@GabrielBenamy 8 hours

yay site-analytics

Gabriel Benamy

aww, I need 5k rep to see that

Kritixi Lithos

19:30

The page you're trying to visit requires the privilege “access to site analytics.” ;_;

Pietu1998

@GabrielBenamy I once posted a Pikalang answer at 848kB

BlueEyedBeast

I get ~27 more posts for today

Martin Ender

@TimmyD it's not really clear from your explanation at the beginning that we need to be able to detect blocks that are covered by smaller blocks in front of them and what the exact rules are for that. after reading the first part, I assumed I'd always fill solid rectangular blocks of o into the input, before seeing the test cases.

TimmyD

@MartinEnder Thanks for the feedback. I clarified the challenge to state we're only concerned about the corners for detection and the edges and corners for fluffiness.

Gabriel Benamy

someone please stop me from trying to make a code ladder in COW

Martin Ender

19:41

it's still not super clear to me. from test case 5 it seems that one corner can be used for multiple rectangles. and it's also not clear that the edges can hold arbitrary characters. from the spec it seems like horizontal edges should be all - and vertical edges all | but the test cases have horizontal edges containing | (but not vertical edges containing -?)

maybe you might want to use a bigger rectangle than the minimal 4x2 in the spec already

and a test case containing something like this would be good:

|-----|
|     |
|  |-----|
|  |  |  |
|--|--|  |
   |     |
   |-----|

Anonymous

I'm predicting 6 hours

Anonymous

So around 6:45 PM CST (12:45 AM UTC)

Gabriel Benamy

oh damn I just figured it out

wat

asdf

BlueEyedBeast

About 3:30 am UTC

Kritixi Lithos

19:49

What is that in GMT?

Gabriel Benamy

Greenwich-Mean Time

BlueEyedBeast

@KritixiLithos the same time

UTC == GMT

PhiNotPi

My computer science prof seems to like to grade things out of powers of 2. Homework assignments are typically worth either 8 or 32 points.

TimmyD

@MartinEnder Thanks again. Let me know if it's making more sense now.

Martin Ender

looks great :)

Anonymous

19:59

@PhiNotPi Your prof is my hero

Anonymous

I really like how my software engineering professor did tests. Every question had an answer from the lectures and/or readings. If you answered every question with the expected answer, you got 100%. However, if you answered a question with a different, valid answer, you would also get full credit, and possibly more if he thought it was a particularly interesting answer. He believed that, in "fuzzy" subjects like software engineering, reciting information wasn't as important as original thought.

Kritixi Lithos

In my school, I get grades out of 8

ETHproductions

I like both of these profs :)

Kritixi Lithos

20:16

39 submissions to go

wat

Should I buy a OnePlus 3T?

Kritixi Lithos

Buy a Google Pixel

Charges 7 hours in 15 minutes

wat

This charges 8 hours in 30 minutes, good enough

also this is $440, not $650

trichoplax

@wat It has twice as much RAM as my laptop...

wat

@trichoplax It has 1.5x more ram than mine...

trichoplax

20:19

Will you need it?

Nathan Merrill

@wat I'm still on a one plus one, and still haven't felt the need to upgrade

wat

@trichoplax VMs?

betseg

@wat do you know which countries it's available in?

trichoplax

If you run them on your phone then go for it. Personally I just don't need that much on my phone

wat

@NathanMerrill I'm on an iPhone 4S.

@trichoplax That was a joke.

Nathan Merrill

20:20

oh, if you're on an iPhone, then absolutely upgrade

Kritixi Lithos

iPhone is a joke

trichoplax

@wat I never know with people in here :P

wat

@betseg sadly no. I do know that it's a Chinese company.

TimmyD

People are arguing phones? This'll end well.

Also, everyone should use Windows Phone.

wat

@trichoplax There was someone who took an Asus ZenFone 2 (Intel processor) and installed Windows 7 in a VM on it.

Kritixi Lithos

20:22

@TimmyD Haha, very funny

Nathan Merrill

@wat I haven't had any trouble getting it in the US...but I can't speak for europe

wat

@NathanMerrill Isn't betseg in Turkey?

arda

@betseg It wouldn't get through customs :(

Kritixi Lithos

It comes in a few weeks to Europse I believe

Nathan Merrill

no idea

trichoplax

20:23

I think the OnePlus 3 was available in the UK as I half considered it, so I'd guess this one will be too when it's released

TimmyD

@KritixiLithos I wasn't joking. Windows Phone is great.

wat

@trichoplax 399 gbp for 64gb model

arda

@TimmyD Yup

Nathan Merrill

yeah, my parents love the windows phone.

arda

I used to use one, but dropped it to be able to use my pebble

In other news, using HAXM inside KVM causes a BSOD. Nice.

Kritixi Lithos

20:24

Windows phones and iPhones are jokes

El'endia Starman

@Mego Smart guy. We need to get him to teach the HR departments of companies.

wat

@arda ?

betseg

@arda can't we get it even with taxes? ;_;

arda

@KritixiLithos WP is actually good. It's very fast and battery consumption is amazing. But well... can't say that you'll get the newest apps on day one.

@betseg nope. I'll be in germany this summer though, might buy myself one :P

betseg

then i'll want from my uncle

arda

20:27

you'll have to get it added to someone's passport to unlock the imei though

Nathan Merrill

@arda the default apps are pretty good though

arda

or... you know... if you have any spare old nokias...

betseg

@arda ik

wat

Why does Turkey suck so much

feersum

Why would you need an App store? You're a programmer, you should make your apps yourself.

arda

20:29

@wat 7 letters. E, r, d, o, g, a and n.

@feersum Well, the APIs werent so great until the W10 for mobile update.

Kritixi Lithos

@feersum Yes, and spend hours on bugs

feersum

Real programmers don't add bugs.

wat

@arda This him?

arda

@wat yup

Kritixi Lithos

'Automating' comes from the roots 'auto-' meaning 'self-', and 'mating', meaning 'screwing'.

arda

20:31

IDK if @betseg supports him or not, but many people, including me sees him as a major reason of the issues in turkey.

betseg

do you think anyone who supports him knows english? :P

arda

look at the tabela :)

van minut

betseg

> where is kravat

arda

@betseg hahahaha (umm, can you mail me on [email protected])

betseg

^^, ^^^ and ^^^^ some of erdogan quotes

Stewie Griffin

20:33

Re: snippet testing, consider a submission (e.g.) where someone has posted a crack that is invalid, but hasn't removed their comment. I would consider these uncracked, but they do not appear in the list. — DLosc 28 mins ago

^^ Anyone have a quick fix for this?

I can't fix it myself (I only know MATLAB (and some Python)).

wat

@arda k

arda

And for the love of erdogan use pgp keybase.io/ardao

wat

@arda ok so that's what you look like

BlueEyedBeast

@StewieGriffin use the overwrite part of the snippet? I think it has an admin user in it/

Martin Ender

some versions of it definitely do

arda

20:41

@wat yes

BlueEyedBeast

or just flag the comment?

Martin Ender

it doesn't look like this one has the override user feature in it though

trichoplax

It might be nice to have a solution that doesn't require mod involvement

ETHproductions

@StewieGriffin BTW, I modified the PPCG userscript's leaderboard the other day to (mostly) support C'n'R challenges. It only says a challenge is cracked when the OP edited to say it is. (Not that that would help the 99% of people on the site not using the userscript...)

trichoplax

Does anyone happen to have knowledge of how double precision floats vary in results between languages/implementations?

Nathan Merrill

20:44

they vary

that's the extent of my knowledge

trichoplax

I'm trying to settle on test cases that will be achievable for all languages that use double precision, but be as challenging as possible given that requirement

Martin Ender

@NathanMerrill really? in theory, definitely but in practice I think it should be fairly reliable. I'd assume most languages/architectures implement IEEE 754, which also defines how various operations should behave.

trichoplax

I made the mistake of thinking that if I restricted myself to cases that give the same result in Python for both double precision and arbitrary precision, then all languages would match those using double precision

New Main Posts

2

Q: Choose the last card in a poker hand

Poker hands are ranked from best to worst as follows: Straight flush - five cards of sequential rank, all of the same suit Four of a kind - four cards of the same rank and one card of another rank Full house - three cards of one rank and two cards of another rank Flush - five cards all of the s...

code-golf

trichoplax

I've been reading about double precision for IEEE 754, in case there is some leeway in implementation, but it's quite involved...

I might just resort to choosing test cases that work for both python and APL (the language my current test cases don't work for) but I just wanted to double check if anyone had an insight first

Nathan Merrill

20:48

@MartinEnder maybe I don't really know anything about how doubles vary :/

trichoplax

I have a vague idea from previous reading that some implementations use intermediate values with more precision than the operands (or is that some processors...?)

TimmyD

@MartinEnder You can still run into surprises with that, though. Like how .NET uses 15 bits of precision unless you specify full 17 bit precision when doing round trips.

Geobits

What a terrible question for math homework: Lori wants to distribute 35 peaches equally into baskets. She will use more than 1 but fewer than 10 baskets. How many baskets does Lori need?

TimmyD

Between 2 and 9 baskets, inclusive

BlueEyedBeast

@Geobits obviously 4.375 baskets

El'endia Starman

20:53

@Geobits Terrible because there are two valid answers?

TimmyD

It depends upon how hungry Lori is, if she eats some of the peaches before putting them in baskets.

Geobits

@El'endiaStarman Yes, that. I mean, I guess it says "need" at the end, so you could argue five is more correct, but it's still terrible.

feersum

This could be the prelude to a scheme to crack RSA using 3rd graders.

ETHproductions

Perhaps 33 might have been a better number of peaches.

TimmyD

@feersum Lori has 2^74207281-1 peaches ...

2

Gabriel Benamy

20:57

what are we doing

TimmyD

Helping Minibits with homework.

Geobits

Bitching about my kid's homework. Or at least I am :P

TimmyD

By cracking RSA

Gabriel Benamy

sounds fun, what's the problem

TimmyD

The problem is ambiguous wording.

(hah-ha, see what I did there?)

Gabriel Benamy

20:59

:P

TimmyD

Scroll back like a dozen posts.

ETHproductions

The Punmaster strikes again

He's terrible at baseball

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