The Nineteenth Byte

Given an integer N, output the Nth positive number K with the following property in decimal base: For each digit I at position P of K, the number formed from K by removing the Pth digit (i.e. I) is divisible by I. Example and remarks 324 is such a number: 3 divides 24 2 divides 34 4 divides ...

New Main Posts

7:07 AM

0

Q: Define a field with 256 elements

A field in mathematics is a set of numbers, with addition and multiplication operations defined on it, such that they satisfy certain axioms (described in Wikipedia; see also below). A finite field can have pn elements, where p is a prime number, and n is a natural number. In this challenge, let...

code-golf abstract-algebra

Sp3000

8:14 AM

@LeakyNun In any case, you can prove that a*a^-1*b = b via the axioms

Leaky Nun

@Sp3000 Any idea yet?

Sp3000

For?

Leaky Nun

for the field

Sp3000

Golfing it atm

Just taking the algorithm off wiki though, so I'm trying to see if there's better

Leaky Nun

Oh, ok then

@Sp3000 Is it just [0 or 1, a or a+1, b or b+1, ..., g or g+1]?

Sp3000

8:23 AM

What's a, b, ... g?

Leaky Nun

arbitrary.

Sp3000

Not sure what you're trying to represent there, sorry

Leaky Nun

8:37 AM

@Sp3000 Is it xor-multiply and then xor-mod 283?

New Main Posts

8:51 AM

0

Q: Calculate the relativistic velocity

In special relativity, the velocity of a moving object relative to another object that is moving in the opposite direction is given by the formula: In this formula, v and u are the magnitudes of the velocities of the objects, and c is the speed of light (which is approximately 3.0 x 108 m/s, a...

code-golf physics

Sp3000

9:18 AM

@LeakyNun Er... not quite?

For one thing, there's no mod 283

(well, directly anyway)

Hmm actually I guess it is a mod 283

Leaky Nun

Seriously?

Sp3000

Sorry, was just trying to get what you meant by xor-multiply and xor-mod - I'm guessing you mean "xor" in the sense of binary coefficients

Leaky Nun

Yep, that's it.

Sp3000

Woop the %256 was completely unnecessary

But yeah, the "xor-mod" is easier to do as you multiply I think, or at least it is in Python

Leaky Nun

Nice.

New Main Posts

10:10 AM

0

Q: Find operations required to get result

So task is simple, given array of numbers and result, you need to find what operations you need to use on numbers from array , to obtain requested result. Let's make it simple for start, and allow only basic operations such as: addition, subtraction, multiplication and division. Example: Inpu...

code-golf homework

zʏᴀʙiɴ101

> I added homework tag, as this task is inspired by homework ages ago on course.

I think he just wanted to make the homework tag. >_>

People should use the create-tags privilege more responsibly. >_>

muddyfish

removed

zʏᴀʙiɴ101

:D

zʏᴀʙiɴ101

10:27 AM

Good, now burninate the homework tag.

Bálint

@NewMainPosts Can this be solved without bruteforcing?

zʏᴀʙiɴ101

@Bálint -._(._.)_.-

Bálint

I already see myself using a base4 number, and incrementing it

Probably can be solved in less than a hundred bytes that way

Sp3000

You might be able to add a few heuristics in, but I doubt it'll be that much more efficient

(also wondering if the challenge might be a potential dupe)

Bálint

@Sp3000 I think it is, what is the chance, that a challenge like this didn't exist

@Sp3000 It was

Leaky Nun

10:34 AM

Btw, @Fatalize much faster algorithm:

delete = lambda s,i:s[:i-1]+s[i:] if i else s[1:]

def e(n):
	s = str(n)
	for i in range(len(s)):
		if s[i] == '0':
			return False
		rest = delete(s,i)
		if rest == '':
			return True
		if s[i] == '2' or s[i] == '6':
			if ord(rest[-1]) % 2 != 0:
				return False
		if s[i] == '3' or s[i] == '6':
			if sum(map(int,rest)) % 3 != 0:
				return False
		if s[i] == '4':
			rest = '0' + rest
			if int(rest[-2:-1]) % 4 != 0:
				return False
		if s[i] == '5':
			if ord(rest[-1]) % 5 != 0:
				return False

zʏᴀʙiɴ101

@LeakyNun For what? :3

Leaky Nun

The first 100000 (1e5) excludivisible numbers. — Leaky Nun 36 mins ago

Sp3000

o_O not sure half of those optimisations are actually any faster

Leaky Nun

@Sp3000 why not?

Sp3000

1) I'm not sure about the int->str->int going on, 2) there should be more elifs, 3) I'm fairly sure sum(map(int,rest)) % 3 is slower than int(rest)%3 and similarly for 7 and 9

Also delete doesn't look quite right - should it be s[:i] + s[i+1:]?

Leaky Nun

10:51 AM

@Sp3000 thanks, I'll try to convert to base 10 for everything

Sp3000

11:07 AM

Hmm I do think you could probably revamp a few of the shortcuts you have though

Leaky Nun

@Sp3000 Sorry, I don't understand.

zʏᴀʙiɴ101

@LeakyNun How much will 1000000 (1e6) take?

Leaky Nun

@zʏᴀʙiɴ101 Quite long. I'm still optimizing it.

Sp3000

Just thinking aloud atm - e.g. for a digit of 2 you would only really need to check the last 2 digits (the last digit in most cases, the second last digit if 2 is the last digit)

Leaky Nun

Yes, which is what I did

Sp3000

11:09 AM

Not in the above code at least - you're checking for every 2 digit that appears

oh

Hi

Hi

Hi

11:24 AM

Okay now, stop raising the signal noise even a small bit further.

Hi

>_>

<_<

Hi @RenderSettings :)

I seriously can't allocate 50% of the memory of the host PC to a virtual machine.

I wish to use Urbit, but it needs to find 2 GB of memory.

What to do with 1 GB of physical memory? >_>

(On a virtual machine)

RenderSettings

sorry. im not alive right now, on account of it being too damn early o' clock.

ev3commander

11:27 AM

:[

RenderSettings

screw eight ams please

zʏᴀʙiɴ101

Okay. :(

RenderSettings

also, make a swapfile

zʏᴀʙiɴ101

> too damn early o' clock

heh

RenderSettings

it just needs to map 2gb of sequential memory, it doesn't actually use all of that

zʏᴀʙiɴ101

11:28 AM

@RenderSettings I know that

tears off a fresh *Ubuntu VM clone*

zʏᴀʙiɴ101

11:44 AM

I just realized that /dev/sda5, the Ubuntu VM's swap disk, only has 1022 MB XP

2 MB short of the required 2 GB :(

Sp3000

@LeakyNun Nevermind, it was too much microoptimisation for little gain so I gave up :/

New Meta Posts

1

Q: We need a tag for "arithmetic expression building" challenges

There's a popular type of maths puzzle where you get a list of digits (or numbers in general) and need to insert arithmetic operators in order to reach some target number. Every single time we get a challenge around this topic, I think "this looks so familiar, we must've done this before", but th...

discussion tags

LegionMammal978

Hey

Mitch Schwartz

@MartinEnder also codegolf.stackexchange.com/questions/76591/… and codegolf.stackexchange.com/questions/77956/…

LegionMammal978

Note: I have a HUGE 12.2MB 10k by 20k-pixel Mandlebrot set image that I generated for over a week as my desktop background, currently giving it away, ping me if you're interested

Martin Ender

12:02 PM

@MitchSchwartz hm, those are metagolf, but you're right that's actually also related

Fatalize

12:51 PM

Is it me or is SE really slow?

TimmyD

@Fatalize Why not both?

Fatalize

@TimmyD Is it me xor is SE really slow?

Leaky Nun

Chat mini-challenge: find fibonacci(n) in O(log(n)) time code-golf.

El'endia Starman

@Fatalize It's you.

TimmyD

@Fatalize Must be just you, as it seems to be working fine for me. Blame Caching.

mınxomaτ

1:04 PM

Talk about talking (again, but this time from CBC, not Ted): youtube.com/watch?v=_ZBKX-6Gz6A

flawr

@LeakyNun explicit formula?

Leaky Nun

@flawr If you can do it in infinite accuracy, I'll pass.

flawr

I can do it exact

Leaky Nun

Do it.

Poke

isn't it just floor((phi^n)/sqrt(5) + (1/2))

or something

Leaky Nun

1:09 PM

Good luck using that to calculate F(1000000000000)

flawr

I do not see whats wrong with that?

Leaky Nun

Well, float only has 16 decimal places of accuracy

El'endia Starman

Not if you use an arbitrary precision language/library.

Leaky Nun

@El'endiaStarman Well...

flawr

And there is an even easier approximatin for large n

Leaky Nun

1:11 PM

Which is?

flawr

Fibonacci number

In mathematics, the Fibonacci numbers are the numbers in the following integer sequence, called the Fibonacci sequence: 1 , 1 , 2 , 3 , 5 , 8 , 13 , 21 , 34 , 55 , 89 , 144 , … {\displaystyle 1,\;1,\;2,\;3,\;5,\;8,\;13,\;21,\;34,\;55,\;89,\;144,\;\ldots...

Poke

is that not what i said

Leaky Nun

@flawr Alright.

mınxomaτ

@El'endiaStarman Or x87 floats. Slightly higher precision (80 bits). Still not abitrary though

Leaky Nun

@Mego Consider using that.

flawr

1:15 PM

@LeakyNun So what do you need those fibonacci numbers for?=)

Leaky Nun

@flawr Just for fun. I used a base-2 reduction to generate F numbers in O(log(n)) time.

Poke

but assuming you can calculate phi^n quickly that formula is constant time >.>

Leaky Nun

@Poke Multiplication is O(log(n)) time.

at least in Python.

Poke

well that's why i made that assumption

Leaky Nun

It's still O(log(n)) time, no matter how fast you can optimize it.

exp(n*ln(phi)), or base-2 reduction, still O(log(n)) time.

def fast_pow(int b, int n):
    if n<0: return 0
    if n==0: return 1
    if n==1: return b
    temp = fast_pow(b,n>>1)
    return temp*temp*[1,b][n%2]

Poke

1:20 PM

okie

Sp3000

1:33 PM

n->([1 1;big"1" 0]^n)[] (Julia)

zʏᴀʙiɴ101

Language design YANI: action for condition for functions.

As in, return 0 for n < 0

^ == v

if n < 0: return 0

Sp3000

Ruby's basically that, right? Although it's more like return ... if ...

zʏᴀʙiɴ101

Or action if condition.

Leaky Nun

@Sp3000 any docs/stuffs to prove that it is O(log(n))?

Sp3000

Matrix exponentiation is log(n)

Leaky Nun

1:38 PM

@Sp3000 Yes, I know it can be done in log(n). What I am asking is the docs that prove that it is really log(n).

Sp3000

:/ doubt most lin alg systems would document stuff like that

Leaky Nun

Never mind then.

mınxomaτ

My favourite C program: pastebin.com/7EkgxMC9

Sp3000

@LeakyNun github.com/JuliaLang/julia/blob/…

Close enough

But I'd be surprised if any proper language didn't implement it in log

Leaky Nun

@Sp3000 Nice.

Quill

2:00 PM

hey @Upgoat, write a blog post about compilers

New Main Posts

0

Q: The handshake problem

Okay so I've searched for this question and couldn't find it, so here goes. The handshake problem is the classic problem that for n people in a room, if they all shake hands, what's the total number of handshakes that occur. You code should take an input of any number and output the number of...

code-golf math code-challenge arithmetic

Leaky Nun

@Doorknob It was valid.

Doorknob

Yeah, I misread the problem and wanted to make sure it worked for non-integers. :P

Mitch Schwartz

careless to count steps but not count how many operations in each step

Leaky Nun

@Sp3000 Does -0 exist? (ok in some languages there is -0.0 but -0?!)

Sp3000

2:14 PM

Well ignoring the fact that chances are nothing will print as -0, most numeric parsers will still allow int("-0") -> 0, say

Leaky Nun

oh, ok

mınxomaτ

GCC is neat

Mitch Schwartz

we might as well just count the entire calculation as one operation and call it O(1)

Eᴀsᴛᴇʀʟʏ Iʀᴋ

2:42 PM

@Upgoat Serval.

Nathan Merrill

3:04 PM

I tried to disallow -0 as a number, but the problem is that it then it uses - as a unary operator and then 0

Poke

who the hell decided this was a good idea stackoverflow.com/a/7471843/6045282

Upgoat

@Poke blame-dennis-ritchie >_>

Poke

i thought c++ would let me shoot myself in the foot

Nathan Merrill

@Poke that is shooting yourself in the foot

quartata

@Upgoat I gave you the wrong path to extract the config to

It should be /tf not /tf/cfg

That's why it wasn't doing anything :P

Nathan Merrill

3:10 PM

C++ has lots and lots of undefined behavior just so you can do that

quartata

@Poke huh...

Sp3000

Relevant (?): toodarkpark.org/computers/humor/shoot-self-in-foot.html

Upgoat

@quartata wait wat

ok >_>

quartata

@Upgoat Yeah, the zip file contains a folder cfg that's supposed to overwrite the cfg folder in tf

I derped and forgot how it was structured

Upgoat

\o/ apple release OS 11 now my mac can be even slower

Sp3000

3:14 PM

(before anyone complains that there's no golfing languages on the list, here's the entry for APL:)

> You shoot yourself in the foot and then spend all day figuring out how to do it in fewer characters.

Poke

@NathanMerrill If I want to left shift an integer 32 times, i should be able to do that without having to use a larger datatype

Nathan Merrill

ah, but that's not shooting your self in the foot

TimmyD

@Poke That's nonsensical.

Poke

@TimmyD ?

TimmyD

Ints are 32-bit, so you can shift-left 0-31 times

Poke

3:17 PM

How else can I start with 32 1-bits and left shift until i get 0?

TimmyD

set it equal to 0 :p

Poke

yeah but if i'm doing bit logic likely i don't want to be branching when i wouldn't otherwise need to

Nathan Merrill

setting equal to 0 isn't branching

TimmyD

@NathanMerrill pseudocode if(shift-count = 32) { n = 0 } else { n shift-left shift-count }

Nathan Merrill

why is your shift-count ever 32?

TimmyD

3:20 PM

This is the more telling answer for what's happening -- stackoverflow.com/a/7403041

Bálint

3:31 PM

13

A: Weapons of Math Instruction

Javascript ES7 49 bytes a=>a.reduce((c,d,e)=>[c**d,c+d,c-d,c*d,c/d][e%5]) Saved 9 bytes thanks to Dom Hastings, saved another 6 thanks to Leaky Nun Uses the new exponentiation operator.

Why Am I getting so many upvotes on this?

Poke

@NathanMerrill what TimmyD said

flawr

@Bálint Should we remove some?

Bálint

@flawr No, I just want to know the reason

Nathan Merrill

@Poke why is your shift count ever 32?

Poke

My specific usecase is dealing with subnets and netmasks

Bálint

3:32 PM

@uoɥʇʎPʎzɐɹC <- If you were here 5 hours ago, you know why I do this

Poke

the loc was final int netmask = 0xFFFFFFFF << (IPV4_ADDRESS_SIZE - oneBits);

flawr

@Bálint =) people seem to like it, quite often the voting is not really trasparen...

Bálint

40 more rep, and ppcg will be my top community

flawr

@Upgoat plane-crash blame-gravity

Nathan Merrill

@Poke what happens if you do (1 << (IPV4_ADDRESS_SIZE - oneBits)) -1?

Bálint

3:36 PM

@flawr Newton invented gravity => blam-newton

Nathan Merrill

does (1 << 32) -1 work?

uoɥʇʎPʎzɐɹC

@Bálint huh?

Poke

Are you familiar with netmasks?

Nathan Merrill

oh wait, that's the opposite of what you want

00001111 instead of 11110000

Poke

haha yeah

Bálint

3:37 PM

@uoɥʇʎPʎzɐɹC This is why we don't ping random people

Poke

i could use a long, probably

(int)(0x00000000FFFFFFFFL << 32-oneBits)

something like that

uoɥʇʎPʎzɐɹC

@Bálint you're right

Poke

but maybe i'll just use an if statement

it's not an often-traveled branch anyway so maybe it'll be optimized

Bálint

I rewrite my hypercube challenge, so it's more descriptive, see'ya later

22

Q: How to explain atheism in a world where religious miracles are commonplace and spirits visit earth

The world is identical to earth except for the above, which only started happening about 40 years ago. In addition to the miracles there are also a group of humans who have started developing telekinesis and mind reading. The miracles and spirits' strength are not limited to one particularly reli...

culture religion

And a another gem from the worldbuilding SE

TimmyD

> Kansas definitely exists, even if there's no rational explanation for it.

O.o

Bálint

3:47 PM

@TimmyD It's beautiful, isn't it?

How do you call these things in english (the four things after the triangle)

El'endia Starman

Looks like someone got a few coordinates wrong. :P

They're hexominoes.

Bálint

hexomino?

El'endia Starman

Hexomino

A hexomino (or 6-omino) is a polyomino of order 6, that is, a polygon in the plane made of 6 equal-sized squares connected edge-to-edge. The name of this type of figure is formed with the prefix hex(a)-. When rotations and reflections are not considered to be distinct shapes, there are 35 different Free hexominoes. When reflections are considered distinct, there are 60 one-sided hexominoes. When rotations are also considered distinct, there are 216 fixed hexominoes. == Symmetry == The figure shows all possible free hexominoes, coloured according to their symmetry groups: 20 hexominoes (coloured...

Bálint

No, the piece of paper sheet you can make a cube out of

El'endia Starman

Cube nets.

Bálint

3:53 PM

...

I could have think of that

El'endia Starman

There's a section on that Wikipedia page that briefly mentions and shows each of the 11 nets for the cube.

flawr

@El'endiaStarman How about development, would that fit too?

El'endia Starman

@flawr I tried but I can't figure out what you're talking about.

Are you punning on something?

flawr

No, is was asking about anothe rterm for "cube nets".

Or a more general term if you do the same for other solids

El'endia Starman

Well, "nets" is the general term.

Bálint

3:57 PM

0

A: We need a tag for "arithmetic expression building" challenges

I think arithmetic-expression-building-challenge would be a pretty good choice. On a more serious note, arithmetic-permutation would be good.

TimmyD

Bálint

@TimmyD I like that challenge BTW, but mine won't be about nets, I only used it for explanatory purposes.

TimmyD

I'm trying to find a Mathematica post that Martin either linked/wrote over on Math.SE

flawr

@El'endiaStarman In german (so I believe) there is the term Abwicklung which refers to those kinds of nets, but also the "nets" of e.g. curved solids.

El'endia Starman

@flawr Interesting.

TimmyD

4:01 PM

26

Q: Faces and NetFaces relation in polyhedron

I'm trying to generate some plots of polyhedra with coloured faces. To determine the colours, I require the adjacency information of the faces. For the 3D plot this works really well. Say I want to colour the neighbours of a given face: adjacency = Graph[UndirectedEdge @@@ PolyhedronData["Icosah...

graphics polyhedra

flawr

@El'endiaStarman mathworld.wolfram.com/DevelopableSurface.html

El'endia Starman

@flawr Oh, TIL "develop" has a math meaning.

flawr

I just guessed, as "abwicklung" or "entwicklung" can be translated as "development" in totally different contexts=)

Never though of that: Developable surfaces are (obviously) extensively used in ship construction

New Meta Posts

0

Q: Three 'First Post' reviews already reviewed

Title says it all. I just reviewed 3 items that already had a "Welcome to PPCG" comment. Since 2 different people had reviewed them, I assumed that they hadn't forgot to click, "I'm done".

bug reviewing

El'endia Starman

4:18 PM

@flawr Huh, indeed. Of course they'd be useful there.

TimmyD

One more to reopen this question --

6

Q: Simplify a Date

This is similar to simplifying fractions, but with Dates! The input of your program must be of the form mm/dd For example 3/4 //March 4 12/15 //December 15 1/1 // January 1 We assume that the input will be valid such that the months have these numbers of days in them: January 31 February 28 ...

code-golf

Cᴏɴᴏʀ O'Bʀɪᴇɴ

ask and ye shall receive

Upgoat

@Quill okay, but like what part? Making them? Workings of them?

Quill

all, you could do a multi post series

I would say briefly describe all of the components, then do one for each of the components

Nathan Merrill

er mods: If a challenge scoring mechanism gets changed (like a bonus removed), is it ok to edit existing answers with the updated score?

actually, this sounds like a good meta post

Bálint

4:30 PM

Is there a tool, to make matrix images easily?

Upgoat

@NathanMerrill Has there even been a consensus yet? I don't think so, just leave a comment, because what if the user's answer was optimized for the bonus

TimmyD

TIL -- PowerShell [char] casting accepts integers >127 and provided that your console font supports those code points, will happily output the resultant character.

Bálint

*mathermatical matrix

Upgoat

@Bálint like TeX?

Bálint

@Upgoat Is there a good online tex compiler?

Upgoat

4:31 PM

what's wrong with installing a tex app (yes there is i think)

Cᴏɴᴏʀ O'Bʀɪᴇɴ

sciweavers

mathjax

Upgoat

sharelatex.com

Bálint

@Upgoat I don't have that much time

Upgoat

papeeria.com

@Bálint I think you should just type it into math.SE and take a screenshot

or use Grapher app (if you're on mac)

Bálint

@Upgoat I just found a good one without signup

Upgoat

4:32 PM

@Bálint oh, cool. link?

Bálint

@Upgoat codecogs.com/latex/eqneditor.php

zʏᴀʙiɴ101

@Bálint mathURL.com

Upgoat

@Quill okay

lemme find a wordpress plugin that lets me do that

flawr

oh haskell, why are you so difficult???

Upgoat

@PhiNotPi what series plugin do you use on your blog?

Bálint

4:38 PM

@Upgoat This one's better

hostmath.com

Cᴏɴᴏʀ O'Bʀɪᴇɴ

Chat mini challenge: Given a string K, output each character K with N leading spaces, where N is the index of K in the string. Example:

asdf =>
a
 s
  d
   f

PhiNotPi

@Upgoat this one: wordpress.org/plugins/wp-post-series

Martin Ender

@CᴏɴᴏʀO'Bʀɪᴇɴ CJam, 9: leeSf.*N*

TimmyD

@CᴏɴᴏʀO'Bʀɪᴇɴ PowerShell, 36 bytes -- param($n)0..$n.length|%{" "*$_+$n[$_]}

Cᴏɴᴏʀ O'Bʀɪᴇɴ

J, 9 bytes: (' ',])/\

Upgoat

4:40 PM

@PhiNotPi cool, thanks

zʏᴀʙiɴ101

@PhiNotPi Why didn't anyone rate the compatability?

TimmyD

PowerShell, 31 bytes -- [char[]]$args[0]|%{" "*$i+++$_}

Martin Ender

@CᴏɴᴏʀO'Bʀɪᴇɴ Retina, 10 assuming alphanumeric input: retina.tryitonline.net/#code=XEIKwrYkLmAkKiA&input=YXNkZg

TimmyD

I've never done three + in a row before, that's cool.

zʏᴀʙiɴ101

Just register or log in, find out the WP version and plugin version, and vote.

quartata

4:49 PM

@CᴏɴᴏʀO'Bʀɪᴇɴ Can the output be like ['t', ' e', ' s', ' t']?

If so then Pyth 7 .e+*dkb

If not Pyth 8 bytes j.e+*dkb

Cᴏɴᴏʀ O'Bʀɪᴇɴ

nvm 7 byte is okay

quartata

All right?

Sp3000

++++++++[->++++>+<<]>>++<<,[<[-<+>>>.<<]<[->+<]>+>.>>.<<,]

Cᴏɴᴏʀ O'Bʀɪᴇɴ

impressive

Sp3000

Better layout: ++++++++[->++++<<+>]<++>,[>>[->+<<.>]>+[-<+>]<<<.<.>,]

(probably one of those rare BF-beats-Java moments?)

Cᴏɴᴏʀ O'Bʀɪᴇɴ

5:03 PM

we need a java golfer in her right now

*here

<_<

quartata

You don't want to see it

Cᴏɴᴏʀ O'Bʀɪᴇɴ

Of course I don't want to C it. It has no class

:P

quartata

String f(char[] c){String r="";for(int i=0;i<c.length;i++){for(int n=0;n<i;n++){r+=" ";}r+=c[i]+"\n";}return r;}

I hope the trailing newline is OK

Cᴏɴᴏʀ O'Bʀɪᴇɴ

it's okay

quartata

112 bytes

Cᴏɴᴏʀ O'Bʀɪᴇɴ

5:19 PM

@Sp3000 yes, it is

quartata

Java has no string multiplication so

Sp3000

I'd pull a primo for the initial constant building, but I dunno how shrugs

quartata

I tried it with just printing the spaces out and printing c[i] with a newline but it's longer

The char[] instead of a String shaves a lot of bytes off though

Cᴏɴᴏʀ O'Bʀɪᴇɴ

surely it has a library for string mult?

quartata

no

mınxomaτ

5:26 PM

Dunno if this is valid in Java

Isnt

Bálint

@quartata remove the space between char[] and c

And also, you could create a lambda

FryAmTheEggman

@quartata slightly better Pyth: j+V*R;l

Bálint

5:52 PM

How can I make an image smaller in an answer?

Bigtoes

Meh:

String f(char[]c){String o="";int i=0,j;for(;i<c.length;o+=c[i++]+"\n")for(j=0;j<i;j++)o+=' ';return o;}

Mainly just killing braces and moving stuff around from quartata's.

Bálint

@Bigtoes meh

c->{String o="";int i=0,j;for(;i<c.length;o+=c[i++]+"\n")for(j=0;j<i;j++)o+=' ';return o;}

Bigtoes

There's really not any better way to do it I can think of though.

Yes, lambdas work for cheap gain, as usual. I don't use them for java golfing though.

Upgoat

@Bálint use img tag

Then specify with and or height

Bálint

@Bigtoes "Cheap gain" is almost 15 byte

mınxomaτ

5:55 PM

C# would be pretty good here, but I'm too lazy

Bigtoes

@Bálint I mean "cheap" as in shady, not insignificant.

All it does is move the function signature to a different part of the program imo.

Bálint

Javascript is awesome here

wizzwizz2

@Chatgoat Where are you?

Bálint

c=>o="",eval(`for(i=0;i<c.length;o+=c[i++]+"\n";o)for(j=0;j<i;j++)o+=' ';`)

And could be even shorter, if I would care to change for-s to map-s

@Upgoat How can I do that?

mınxomaτ

@Bálint for(j=0;j<i;j++)o+=' ';, why not use .repeat?

Bálint

6:03 PM

@mınxomaτ Again, I couldn't bother

If I want to, I could bring it down to 20-25

@Upgoat Nvm

zʏᴀʙiɴ101

@wizzwizz4 Where are you? :/

Bálint

6:20 PM

Strange, I posted a sandbox post 2 minutes ago and it didn't announce it

flawr

Kids Explain Art to Experts: Chris (7) vs. Mondrian | Name That Art

►

TimmyD

@Bálint The feed only runs like every 15-20 minutes

flawr

another one of those: youtube.com/watch?v=A5jn4yamjec

New Sandboxed Posts

1

A: Sandbox for Proposed Challenges

Rotate a hypercube graphical-output geometry math ascii-art Introduction A hypercube/tesseract is the 4 dimensional equivalent of a normal cube. It's made by taking a cube net, extending it to the 3rd dimension, then – using the 4th dimension – folding it into a hypercube. It's basically a cub...

TimmyD

6:38 PM

Chat mini-challenge -- given an ASCII string, output the product of each of it's char-codes' digit-sums. code-golf ... For example, for input "Foo" (ASCII 70, 111, 111), output 63 because [(7+0)*(1+1+1)*(1+1+1)]

PowerShell v2+, 62 bytes -- ([char[]]$args[0]|%{[char[]]"$(+$_)"-join'+'|iex})-join'*'|iex

New Meta Posts

0

Q: What causes an edit to deviate from the original intent of the post?

After seeing that this edit suggestion got rejected because it "deviates from the original intent of the post", I realized that I have no idea why or how an edit could change the sense a post makes. What causes edits to do so on PPCG?

discussion support editing

Poke

Java, 99 bytes -- `int a(char[]a){int s=1;for(int b:a){int t=0;for(int c:(""+b).toCharArray())t+=c-48;s*=t;}return s;}`

:s ?

probably could be golfed more

proud of my smiley face in there c:

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