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6:33 AM
@JohnDvorak odd = prime confirmed:)
3 hours later…
9:41 AM
A: Sandbox for Proposed Challenges

Kevin CruijssenDo the 26 richest billionaires own as much wealth as the poorest 3.8 billion people? code-golfnumberinteger Introduction: I just read this post with the same title when I came across it in the HNQ. In this question it is being discussed if the claim of president-candidate Bernie Sanders, who c...

3 hours later…
12:44 PM
A: Sandbox for Proposed Challenges

User AH interpreter H is a relatively simple language that does not implement advanced features. Create an interpreter for H. The winning criterion for this challenge is code-challenge. Here is everything in the H command reference just for reference purposes: Def The def command is used to define...

3 hours later…
3:47 PM
A: Sandbox for Proposed Challenges

l4m2Enable 2-char Jsfuck Provide a shortest code that makes JavaScript able to do everything JavaScript is supposed to do, with only [ and ]. You can choose your environment(FF/node/etc). Answering in 6-char JsFuck or something similar is welcomed.

2 hours later…
5:29 PM
I recently discovered toolz, a Python library for functional programming, and I have fallen in love with it
5:51 PM
Any mod feel like updating the site name mentioned here?
6:07 PM
@Mego @DJMcMayhem @Dennis ^
Should I say "Code Golf & Coding Challenges", or just "Code Golf"? I prefer the second
I like Code Golf
> Code Golf
but be sure to put it in italics
oh, and there's one at the bottom too!
btw, the italics are important in that page because PPCG might be somebody's first interaction with SE, but they might already know what "code golf" means, and then they could be like "um... wut" otherwise
6:15 PM
Needs to be in 72 pt. Impact Bold
Gotta be subtle, ya know?
btw, it might be time to get this off the Featured list
I like S͟U͟B͟T͟L͟E͟T͟Y͟ too
inb4 "w?h?a?t? ?a?r?e? ?y?o?u? ?s?a?y?i?n?g? ?t?h?e?r?e???" :D
If anyone wants a better visual of the new header, you can go here: https://cdn.sstatic.net/Sites/codegolfmeta/img/header-background-image.svg?v=7b61cc011d06

and run:
var allElements = document.getElementsByTagName("*");
for(var i = 0; i < allElements.length; i++) {
var element = allElements[i];

if(element.getAttribute("fill")) {
element.setAttribute("fill", "black");
@DJMcMayhem Subtle. Like the b.
6:29 PM
A: Sandbox for Proposed Challenges

GiuseppeImplement ave This is one part of a multi-part series inspired by various built-ins in R. Credit goes to digEmAll for suggesting this one. ave calculates particular grouped values of a list. For example, we would group x in the following way based on the criteria given in f: x = [2, 1, 3, 5...

It's funny, the word "subtle" looks correct to me, but no matter how many times I double check the word "subtlety", it looks like it's spelled wrong to me.
Subtle Tea
6:52 PM
If I have a directed graph generated from permutations and it is generated as integers from 1 to "n". I have the original sequence and I need to check if that sequence can be constructed from the graph. for example lets say the permutation sequence is [4,1,5,2,6,3] and our adjacency matrix for our graph is {1:[5],2:[6],5:[2],4:[1],6:[3]} Would the Hamiltonian path in the graph be considered the original order of the sequence assuming we have the correct starting vertex?
If I understand what you're saying, then yes
I'm kind of confused about your specification for the adjacency matrix though
thank you!! I thought I might have been losing my mind there for a second
I think it would be easier to understand if you put it in order, like {4:1, 1:5, 5:2, 2:6, 6:3}
@ThePlasmaRailgun well it's a directed graph the sequences are like this [[5,2,6,3],[4,1,5,2]] but I interperate it as this {1:[5],2:[6],5:[2],4:[1],6:[3]}
Yes, but that's the exact same adjacency matrix, just slightly shuffled so it's easier to just look through and verify it follows a hamiltonian path equivalent to your permutation
6:59 PM
@ThePlasmaRailgun good point that would have made it a lot easier
@ThePlasmaRailgun are there any nice theorems for a Hamilton path
Also, you might want to look at Rook generators, which are polynomials generating the number of possible matrices where every nonzero value is a 1, and every row and column contains only a single 1, no more, no less.
That ends up being a problem of how many possible permutations there are
Ignoring rotations and mirrorings
Which is an interesting little twist that can end up being useful
nice! will do that
If you're interested specifically in permutations where no element stays in it's original place, that's called a derangement problem, and there is also a formula for it, it ends up being equivalent to a similar "rook problem" where placing 1s in the diagonal is forbidden
derangement problem is this mostly used in encryption or decryption
It's used in a lot of things
IDK about encryption, I don't think it's in any major algorithms
Anytime when you want to reorder something so that the elements are not in original order, that's derangement
7:08 PM
sorry what I really meant what kind of problems is it mostly used toward solving
Here's wikipedia's example: Suppose that a professor gave a test to 4 students – A, B, C, and D – and wants to let them grade each other's tests. Of course, no student should grade his or her own test. How many ways could the professor hand the tests back to the students for grading, such that no student received his or her own test back?
It really ends up being used almost anywhere permutations are used, because it's just a slightly restricted permutation
interesting so distribution at scale
Random permutations are used pretty often in interleaving and deinterleaving, which are methods to make signals more robust
Interleaving is frequently used in digital communication and storage systems to improve the performance of forward error correcting codes. Many communication
channels are not memoryless: errors typically occur in bursts rather than independently. If the number of errors within a code word exceeds the error-correcting code's capability, it fails to recover the original code word. Interleaving ameliorates this problem by shuffling source symbols across several code words, thereby creating a more uniform distribution of errors.[12] Therefore, interleaving is widely used for burst error-correct
@ThePlasmaRailgun thanks a lot that really did help! :)
No problem!
7:29 PM
Q: Write an interpreter for H

User AH is a text-based, weakly-typed language. Create an interpreter for H. The winning criterion for this challenge is described in popularity-contest. Here is everything in the H command reference; the command reference of H is very hard to navigate through, and some parts are missing. Please do ...

8:11 PM
A: Sandbox for Proposed Challenges

wrymugFind the closest hex color shorthand In CSS, colors can be specified by a "hex triplet" - a three byte (six digit) hexadecimal number where each byte represents the red, green, or blue components of the color. For instance, #FF0000 is completely red, and is equivalent to rgb(255, 0, 0). Colors ...

@EriktheOutgolfer Yeah, I remember seeing that too and thinking the exact same thing
And should this still be pinned?
it will be unpinned in a short while, 14 days have almost passed
Oh, okay
Give it 6-8 weeks.
6-8 weeks
Why is 6-8 weeks the default time for anything on SE
8:21 PM
A: The Many Memes of Meta

Robert CartainoMeme: 6 to 8 Weeks Originator: Jeff Atwood First Heard: May 13th, 2008 Cultural Height: In about 6 to 8 weeks Definition: The time estimate given "off the top of my head" when the Stack Overflow team has only a vague idea of how long a task will take because they have little-to-no formal sche...

There should be a challenge for parsing HTML
@MilkyWay90 Using regex?
Then somebody would submit a regex answer
@Adám Yes
@MilkyWay90 He comes.
Then bobince would join PPCG
Tony the Pony He Comes
That should be a horror movie name
"We've just got to parse this webpage for hidden contents!"
makes regex
"What is that in the distance?"
"A-a pony?"
Zalgo covers his screen
"Tony the Pony!"
8:24 PM
@MilkyWay90 Btw, that should be closed as unclear. Define HTML!
@Adám pastes entire HTML specification
@MilkyWay90 Which one?
@Adám yes
But yeah, It would exceed SE's 30000 char limit
My inbox is getting littered with my SO meta posts
8:26 PM
@MilkyWay90 Not to mention, it'd fail on a lot of web pages. E.g. <i>x<b>y</i>z</b>
@Adám Or no trailing tags
@MilkyWay90 *65536 :D
@MilkyWay90 An actually viable target would be X(HT)ML.
@EriktheOutgolfer It's been upgraded?
8:27 PM
what? that's just PPCG's custom char limit for posts
@Adám Okay
@EriktheOutgolfer Oh, I thought it was the same for all SE posts
in fact, meta still has the 30000-char limit
There we go, finally fixed all the typos after 4 attempts
@EriktheOutgolfer That was a typo, I meant SE
We should probably make a meta post explaining what PPCG is now that our official abbreviation is CGCC
Because a lot of people (including me) will keep on using PPCG
or we can edit Adám's
@EriktheOutgolfer Adám already made one?
8:31 PM
long ago
Oh yeah I remember seeing that
It was an answer for explaining all of the PPCG terms
Q: What are the PPCG specific abbreviations and terms?

AdámNewcomers to PPCG are often compelled to ask what many of our abbreviations and terms mean. Let us list them here so this information always will be easily available.

@EriktheOutgolfer Okay, edited it
> CGCC: Programming Puzzles & Code Golf
@MilkyWay90 It was already on the list, but I've updated it now.
8:35 PM
Oh whoops
@MilkyWay90 I'll fix it.
@Adám MilkyWay90 added the CGCC abbreviation which wasn't already there though... I'll add that in
oh lol ninja
@EriktheOutgolfer It was added wrong, btw.
@Adám yeah, the part I quoted above :D
8:38 PM
The SE glossary is amazing
@EriktheOutgolfer Oh. I see that now.
The people who contributed had a lot of commitment
And they have reprex there too
you mean SO?
imo, "reprex" isn't as good as the good old "MCVE"
> but... my question doesn't have to go with reg... oh, rePRex... wut
For the glossary
I thought reprex isn't in use
Because it's the most downvoted question in SO Meta
it's been forcefully established, that's why
8:41 PM
Q: Min-Reprex: a less awkward name for MCVE

Shog9 Update: ok, ok, this was a wee bit premature - here's the follow-up proposal: MCVExit redux: I don't need a milkshake to know when I've missed the mark Five years ago, we set out to write up some guidelines for folks asking debugging questions on Stack Overflow. Andrew Thompson, auth...

Oh that's min-reprex
But I remember reprex being disliked too
@EriktheOutgolfer It seems to be redirecting [mcve], [reprex], etc all to the same help page
So I don't think it's been forceful
it's still the "official" term, although I'd still use "MCVE" over "reprex", the latter is confusing and looks a lot like "regex"
> The full title is long, and the initialism is... Also long
> reprex
the heck kind of argument is that
reprex is longer than mvce
@Poke I think they are counting in syllables
also, "MCVE" can be a mnemonic, while "reprex" is more like just the "VE" part
Reprex sounds too much like "regex" for me to recognize it as minimal reproducible example quickly
8:49 PM
in fact, "MCVE" says more than either "reprex" or "MWE"
I like how April Fools meta posts are always closed as "problem cannot be reproduced"
otherwise the close reason would be shoved in the comments
9:32 PM
Had a project on production since late 2017. Yesterday, client tried to update some stuff on their server and moved a bunch of folders around, even the ones they've been specifically told to leave alone; project broke. Rolled everything back, project is still broken. Now I don't know whether I'd rather shoot myself or the client.

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