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5:00 PM
uhh
Without the hat:
:p
JS console ftw
 
I know that is what you really look like.
 
Why is that scratch code?
 
because
 
Not like JS, python or a text langauge?
 
5:01 PM
nope
 
Do you know Scratch
 
Do you know anything else?
 
that's my real icon
@RikerW Yes. js, snap!, python, java, c++, etc
 
You changed you name from ev3commander, right?
 
5:02 PM
@RikerW Yes check my profile
 
So you have an EV3?
 
yes
why does chat automagically hide duplicate posts
 
I know, I hate it.
 
Huh, it works if you change thE CASE
 
ideone is not working! we are all going to die!
 
5:05 PM
It ignores whitespace though, so 'yes' is the same as 'yes '.
@TanMath Never use ideone. :P
 
why not? what do you use then?
 
Repl.it is worse, it always crashes my browser.
@TanMath I click run, and it takes like 5 minutes to finish executing my code.
Even for just like printf("Hello, World!");
 
oh god
Use coderpad.io for collaborating
 
wat?
@BlockCoder1392 Yes, but watch out for steve.
 
5:10 PM
About steve:
 
So yesterday I think Calvin's Hobbies posted a link to another chat room.
It is called miauo.
 
coderpad does not work... ideone was the best...
 
It is like here, but for off topic chatter.
So then he posted a coderpad link .
Everybody migrated to there.
 
@RikerW miaou
 
5:11 PM
I know, I am too lazy to edit.:P
So we screwed around on codepad until it was only Me, Adnan, and Conor left.
 
Lets Go away from this offtopicness right now! coderpad.io/AD7XY7GT
 
Conor was afk though, but was still shown in the bottom bar.
 
no...
 
what will i do with my life without ideone??
 
@TanMath Actually have a life? :P
 
5:24 PM
@RikerW of course I do! it was a joke!
 
@TanMath THen why are you still here with us no-lifes???????? :P
 
@RikerW because I want to see what you guys are doing! any problem with that?
 
one time i was on a site like ideone (it may actually have been ideone i don't remember) and i was like "i wonder if there's an easter egg if i do os.system("rm -rf /*")"
1. there was not
2. the site immediately went down
i'm certain it was a coincidence but i was so scared haha
 
test cases and stuff is done... any last comments before I post it?
6
A: Sandbox for Proposed Challenges

Martin BüttnerImplement XOR sort code-golfarray-manipulationsortingbitwise Conceptually, this challenge is really simple. You're given list of non-negative integers ai. If possible, find a non-negative integer N, such that the list consisting of bi = N XOR ai is sorted. If no such N exists, output should be ...

@trichoplax thanks
 
5:36 PM
@MartinBüttner looks good to me
and a cool idea
 
thanks :)
I really wonder if this has been studied at all and if there are more suitable operations
 
Wow. Just opened the extra test cases. I'm tempted to add in another "very" in front of "very large"...
 
it could make a nice tricky question if we find a problem whose numbers are always xortable
 
that sounds like something peter taylor would know about, but i don't know if that's true or if peter taylor is in my head as "smart ppcg guy"
 
@trichoplax since I'm looking for (pseudo)linear solutions, so I'm not even sure those test cases are big enough.
 
5:40 PM
like finding the one number in a list with no duplicate with O(1) extra memory
 
@randomra I'm tempted to rename the challenge to "Xort an array" ;)
 
@MartinBüttner You should. Cooler names make cooler challenges.
 
Definitely. Go for it.
 
@randomra That can be done in m*n time. Where m is the difference between the maximum value and the minimum value.
And n is the number of elements
 
will have to be "xorting"
15 characters and stuff...
 
5:44 PM
Those are indeed very very large test cases O_o
 
12k elements
how did no one notice that my three test cases were actually four? :P
 
5
Q: Xorting an array

Martin BüttnerConceptually, this challenge is really simple. You're given list of non-negative integers ai. If possible, find a non-negative integer N, such that the list consisting of bi = ai XOR N is sorted. If no such N exists, output should be anything that can't be mistaken for a valid N, e.g. a negative ...

 
Goodbye for now
 
@SuperJedi224 oh and O(n) time
 
6:00 PM
@Dennis I finally got the Dennis numbers approved on OEIS! oeis.org/A263172
15
 
YAY!!!!!
 
> Called Dennis numbers as a tribute to user Dennis for winning the robbers' part of The Programming Language Quiz of the Programming Puzzles & Code Golf Stack Exchange website.
haha, very nice
 
Who is Matthew McCaskill?
 
me
 
Okay.
 
6:06 PM
:O
 
6:20 PM
@GamrCorps \o/
 
6:30 PM
9001 years later...
 
6:53 PM
@GamrCorps One of my favourite things about this is that they used @Doorknob冰's Rust program. It seems fitting that a sequence that came from PPCG would use golfed code (with some added whitespace, but still) :)
 
oh, ha, I didn't even notice that
great, now people will think that's how I write all of my code :P
 
i was not sure if that would ping you or not, haha
i wish i knew mathematica so i could find some (non-trivial) bytes to save in that program :P
It's been a while since I read the original Dennis Numbers challenge
I'm surprised 212 is not a Dennis number, rather than trivially a Dennis number.
 
@randomra You didn't originally specify that.
 
By the way, can we use "Dennis" as a property of a number? Then my last message could have been:
> I'm surprised 212 is not Dennis, rather than trivially Dennis.
2
And that's awesome.
 
 
1 hour later…
8:03 PM
Quiet in here today...
 
Sure is.
 
True dat
 
want me to start chatting?
 
ok
 
8:17 PM
phew - that was close ;)
 
haha
Ugh, cmake is using all 4 cores at near-100% which means I can't see what I'm typing right now and also I'm experiencing xkcd's "Compiling"
 
What are you compiling?
 
emscripten
 
8:32 PM
@GamrCorps Hi
 
Hi
 
guys I need a better title for this question:
3
Q: Do the Chain Rule

MaltysenWe've had a lot of challenges on differentiation and integration, but none on just solving related rates problems. So in this challenge, you will get a bunch of derivatives (They will be numeric, not in terms of any variables) and have to find another derivative. The input will come in a newline...

it sounds pretty stupid right now
 
3
Q: Do the Chain Rule

MaltysenWe've had a lot of challenges on differentiation and integration, but none on just solving related rates problems. So in this challenge, you will get a bunch of derivatives (They will be numeric, not in terms of any variables) and have to find another derivative. The input will come in a newline...

 
8:48 PM
"Do the Chain Rule" sounds like another bad 70's dance move.
 
How about "Solve a System of Related Rates Equations"?
 
@mınxomaτ I agree, but that's also why I like it
 
@undergroundmonorail I'll keep it if you upvote :P
 
my mouse was on the way to the button already when the notification popped up
:P
 
rep cap!
 
9:04 PM
@Maltysen "The why? The x!"
2
 
9:20 PM
Those two girls in the latest xkcd should have been beret guy.
 
How much do you wanna bet that some PPCG member will see that and make a language based off of that?
 
...
$0.
 
Can someone help me with HTTP Headers?
 
What do you need?
 
9:48 PM
> 1 is superior to urine.
hahaha :P
 
hahahhaha
 
10:11 PM
1 hour later..
 
Not quite.
 
Close though
 
0.00080128205 dog years later...
 
-1 days earlier...
 
Isn't that the same as 1 day later...?
 
@Maltysen ...wat
@Jakube Your xorting Pyth answer is awesome :D
 
@AlexA. Thanks. Finding the most significant bit is quite stupid at the moment though.
Maybe there's something better
 
That challenge seems difficult enough to me that I wouldn't call any part of any working approach stupid. :P
 
It is at the first look. I had no idea at first.
But when I experimented a little bit with the binary representation of the first example, I quickly saw the necessary pattern.
 
10:48 PM
I'm still not entirely sure I understand the approach so it's kind of like magic to me.
 
@Jakube it has a bunch of algorithms for finding the MSB too
 
> Bit Twiddling Hacks
wth is "bit twiddling" and why must it be hacked?
 
@MartinBüttner Thanks, but this will be not necessary. I just found a 5 byte short MSB solution by using the logarithm base 2. I doubt that this can be beaten.
 
@Jakube yeah that's what I did in my CJam reference implementation too
 
11:13 PM
@NewMainPosts This Xorting challenge has one of the largest discrepancies between question votes and answer votes I've ever seen.
 
@MartinBüttner Can we assume that the input will have length > 1?
 
11:30 PM
user image
6
 
@MartinBüttner Btw, I really enjoyed your problem. The solution is really elegant, but not obvious at all. One of the most inventive problems here on PPCG that I've seen in a long time. Only too bad, that so few lists have this property.
 
@ThomasKwa It certainly wouldn't be at all competitive, and would alos be extremely slow
 
That's not the question. The question is whether it's possible.
 
11:41 PM
But you could use a BigInt dialect of Brainf*** to implement a hyperexponential function
And convert that
Goodbye for now
 
0
Q: Julia equivalent of Ruby's each_cons

Alex A.In Ruby there's a method each_cons, which can be used to iterate over consecutive groups of a given size. For example, irb(main):001:0> [4, 7, 6, 1, 0, 3].each_cons(2) { |x| p x } [4, 7] [7, 6] [6, 1] [1, 0] [0, 3] => nil Here we're selecting and printing each consecutive pair of elements from...

Summoning the Julia users
2
I know you're out there
 

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