4:02 PM
For the record, DṂ did exist, but it only worked for monads. The commit implemented Þ, ÐṂ, ÐṀ for dyads is dated May 9, 2017. — Dennis ♦ 19 hours ago
@Dennis I knew there'd be a good reason why you didn't have the 3-byte version. We were wondering about that in chat too, so thanks for the useful information! — Mr. Xcoder 12 hours ago
@EriktheOutgolfer

Oh ok, sorry for pinging then
Also my solution will never fail because two consecutive positive integers are always coprime
I'll add that to the post

or because the list contains 1 which has gcd 1 (i.e. is coprime) with every other positive integer

Or that

Wait >_> that's just a port of xnor's original solution

4:18 PM
CMC: Given a positive integer, check whether it is an Evil Number.

jelly, 4 bytes: BSḂṆ

Truthy: 0, 3, 5, 6, 9, 10, ...
Falsy: 1, 2, 4, 7, 8, ...
@EriktheOutgolfer Nice

@orlp I messed up in my logic so numbers are correct, but all y-coordinates are positive. Haven't tried to fix it.

@Mr.Xcoder how can you typo "Nice" with "list"???

@EriktheOutgolfer Two keys away, nearly all of them lol :-)

4:20 PM
three
and n is 3 away from l

@EriktheOutgolfer 3 bytes
Wait...
Why do you need
Like, 0 -> truthy, 1 -> falsy

but that's not the case with jelly, and it's normally not allowed

Oh ok then

btw an alternative would be BS2ḍ
or even BḊSḂ I guess

8 bytes in Pyth... Ugh
Seems too long maybe?

4:24 PM
!%sjQ2 2 right?

!%sjQK2K or !%sjQ2 2
Yeah
Added that fancy explanation for something obvious :-/

@Emigna why not?

Progress! Noodle9’s trick offers a 44-byte solution: n=0;exec"print~int(bin(n),13)%2+n;n+=2;"*400Lynn 5 mins ago
yay!

@Lynn Woah nice!

@orlp Been making dinner :P Will see when I have time/feel like fixing it

4:27 PM
I still think some arithmagical nonsense is gonna turn out to be shorter.

like, outgolf xnor? :D

CMC: post a CMC that pushes what counts as a valid CMC as hard as possible.

@ASCII-only Beat these records: 1. It takes ~15 minutes to boot (well not exactly true, but once in ten times) 2. Contains hell lot of unnecessary blotware. But unnecessary, they're not only unnecessary, but harmful too...

@Lynn 1. Woah 2. How does this even work

Any other code golf sites aside from PPCG and golf.shinh.org/u.rb?

4:31 PM
@AlexKChen bloatware is in all windows computers...

@ASCII-only Converts it to base 13, since b is the second last "digit" in the set of base 13, and 12 is even, so it cannot be used instead.

@JohnDvorak CMC: Find a prime larger than 2^74,207,281 - 1
12

@Mr.Xcoder yes, too many

@ASCII-only But...well I give up... Lenevo loses to Acer+Pando combination hands down..

Then takes its bitwise complement and mods by 2

4:32 PM
@Mr.Xcoder right

Actually c is the last base-13 digit but we need an odd base so 12 doesn’t work

@Lynn Oh yeah you're right

we need an odd base so that modulo 2 the computation a 13^0 + b 13^1 + c 13^2… reduces to a ^ b ^ c …

@AlexKChen :P I suppose it could stop be very bad, but I'd say it's a software problem, and maybe you have a lower end computer

and b happens to be an odd digit, which is why we bitwise complement before taking the mod 2 to flip the parity again

4:34 PM
I was thinking of using differences, but can't find a pattern

Umm, if we get the deltas, the 2's are either 2 or 4 places apart from each other

The 2s?

The differences aren’t very useful

I don't think that's relevant though

Also the even numbered ones have a delta of 2 or 3, and odd ones have delta of 1 or 2
Oh well

4:36 PM
Yeah, will never be golfier than the arithmagical nonsense -- Lynn

@Mr.Xcoder what.

nvm

There's kinda a pattern but not really tio.run/…
It appears to be a self similar sequence actually tio.run/…

yes it is I discovered it too

But we only have 10 bytes left so not enough

4:45 PM
actually it's that you start with [0] and then each iteration you append the list with every element xor'd with 1 to the existing list

so it goes like [0] -> [0, 1] -> [0, 1, 1, 0] -> [0, 1, 1, 0, 1, 0, 0, 1] -> ...

I can’t tell what you’re trying to do, but that’s the Thue–Morse sequence!

Oh so Arnauld's already mentioned it

4:47 PM
@EriktheOutgolfer Well if you running it in Kolomogrov complexity time of O(n^n) it works fine though.
But it works better in the data structure of pyth

37 seconds.
@EriktheOutgolfer ^ I was trying to see how long I can speak blabber regarding to programming. It lasted 37 seconds in TNB

@EriktheOutgolfer Binary solo!

@AlexKChen you sound like a markov bot

@AdmBorkBork see this for how it works generally it's like thue-morse sequence
the argument is iteration

4:52 PM
@EriktheOutgolfer From a Flight of the Conchords skit

5:08 PM
Actually

@AlexKChen you deserve a second try

The Thue Morse sequence is in the sequence already
The only problem is you need the numbers from one step in the future, which is three steps in the past, either way it's too long

Well... not really, but it's more fun for us that way.

@JohnDvorak Yeah I'm trying it on chat.stackexchange.com/rooms/71/the-h-bar . 8 minutes and still not spotted ;-)

:@alex I'll enjoy watching that: P

5:11 PM
CMC: Given two positive integers X and Y, return (X * (2 ** Y)) - 1.
Where ** means power.

jelly, 3 bytes: æ«’

17 in Python

x=y=>x*2**y-1

@Pavel x=>y=>x<<y-1
I think?

IDK.

5:13 PM
5, 8 -> 640

pyth, 4 bytes (takes as list): t.<F
or one that takes in reverse order: t.<E

What!??!

@Mr.Xcoder Works, thanks
Actually no

No
I am wrong?

I confuse
@Mr.Xcoder Try it with 5, 8

5:14 PM
1279 is correct

and 05ab1e doesn't have shifts

@JohnDvorak They still hadn't figured out I am keeping writing complete nonsense :P

Oh ok
._.

@alex maybe they're just too polite to call you out

5, 8 -> 1279

5:15 PM
hmm... I gotta try it on MSE chat after dinner.
stay tuned for the fun.

@EriktheOutgolfer Wh... How does - take precedence over <<?
Any idea?

@Mr.Xcoder dunno js

@EriktheOutgolfer In Python

05ab1e, 3 bytes: so*

@AlexKChen toss me the link then

5:16 PM
Python, 19 bytes: lambda x,y:(x<<y)-1

@Mr.Xcoder doesn't?

lambda x,y:x<<y-1 doesn't work?

Sorta surprised it worked in Proton because Proton is heavily based on Python

@EriktheOutgolfer It doesn't

5:17 PM
I didn't use Python's OOP
I think

1 min ago, by Mr. Xcoder

also sorta surprised that people remember proton exists lol

TBH whenever I use proton I just write a python solution first and then substitute in the sane lambda syntax.

@Mr.Xcoder wait a sec

hi everyone

5:18 PM
I think you've derailed them so hard they're unable of a word @Alex

hi @LeakyNun

nope, both python 2 and python 3 have << over -

Hello @LeakyNun

Absolutely no idea why x<<y-1 is not the same as (x<<y)-1

Precedence

5:20 PM
The proof that it does take precedence: 5*(2**(8-1)) = 640

@Mr.Xcoder - has higher precedence

sniped

@LeakyNun Not according to Python wiki

5:20 PM
actually - has higher precedence lol

- precedence over <<

@Mr.Xcoder you're reading them in reverse order apparently

oh we have read them in reverse order

so yes - is over <<

<-- is very confused by the ongoing discussion

5:21 PM
5 mins ago, by Mr. Xcoder
@EriktheOutgolfer Wh... How does - take precedence over <<?

@Mr.Xcoder because << is a bit-level operation

lol

@HyperNeutrino Did you use any OOP?

yes
check proton_parser.py

I thought you mean in the syntax of the language

5:22 PM
@LeakyNun I'd honestly expect bitwise ops to be higher than addition and subtraction

Not in the code for the implementation

although in python that's not the case

me too

@EriktheOutgolfer in which language is it the case?

@orlp none it seems

5:22 PM
@EriktheOutgolfer bitwise is low level
low level = low precedence

I don't think exactly like that

then why does ** take precedence over *?

to be honest, I think in some cases not parenthesizing should give an error

@LeakyNun heh

@EriktheOutgolfer then why is it the case in pemdas?

5:24 PM

@orlp btw I arrived in the uk; where are you?

@LeakyNun In leiden, the netherlands
CMC (first to answer correctly wins): correctly parenthesize a|b<<c*d+e^f>>g&h^j according to Python's rules

@LeakyNun Nice! What is it like there?
@orlp ((a|b)<<(c*d+e^f)>>((g&h)^j)) Incorrect
maybe?
Untested.

@orlp I thought you live in london

@Mr.Xcoder but how do you do the middle?

5:26 PM
Incorrectly.

Sep 8 at 15:57, by orlp
you're not that far from me now, just across the pond, we could meet up sometime :D

@Mr.Xcoder everything is costin' me an arm an' a leg

@LeakyNun I believe you weren't familiar with the saying 'just across the pond'

Pls people delete this!

I was referring to the north sea :)

5:28 PM
@orlp oh lol
@Mr.Xcoder done

Thanks!

@orlp (a|((((b<<((c*d)+e))>>g)&h)^j))

@EriktheOutgolfer You are missing the f

then I'll have to make it anew

And orlp is missing an i :P

5:31 PM
@Mr.Xcoder shhh

@orlp (((a|b)<<(((c*d)+e)^f))>>((g&h)^j))

:D

just a guess
probably wrong

I think that's wrong

sure
it's just off the top of my head

5:32 PM
I think >> has higher priority than ^

@LeakyNun wrong

lol I won't search online
but then I would never get the answer

to be honest the whole point of this challenge is to show that it's silly
I think certain things should be forced parenthesized

is this correct?
(a|(((b<<((c*d)+e))^((f>>g)&h))^j))

5:34 PM
@JohnDvorak The fun should begin chat.stackexchange.com/rooms/36/mathematics (don't tell anything Leaky Nun)

@EriktheOutgolfer appears to be

@orlp (a|(b<<((c*d)+e)^((f>>g)&(h^j))))
God damn Erik
Well mine is different and works

@Mr.Xcoder & > ^

@Mr.Xcoder but not fully parenthesized

5:37 PM
@orlp Good now?

@Mr.Xcoder c*d+e

and you don't just want it to "work", you want it to be parenthesized exactly how python does it itself

what is this?

> (b<<((c*d)+e)^((f>>g)&(h^j)))

ಠ__________________________________ಠ

5:39 PM
@Mr.Xcoder it doesn't though

@EriktheOutgolfer @orlp Both are incorrect
Not just mine, Erik's is too

oops
>>> (a|(((b<<((c*d)+e))^((f>>g)&h))^j))
262153
>>> a|b<<c*d+e^f>>g&h^j
262153
????

@orlp will you be going to the UK anytime?

@LeakyNun perhaps

@orlp (a|(((b<<((c*d)+e))^((f>>g)&h))^j))
ah leaky ninja probably

5:41 PM
but anyway I don't really care :D

it's not like you'd use that anywhere would you? :p

my entire point was that it's stupid
there shouldn't be precedence rules for stuff like this

agree

just left to right

CMC: Given an array of deltas, reconstruct the original list (the initial value must be 0) and then take the minimum value.

5:42 PM
@orlp or just force parentheses
or prefix/polish notation (please don't :p)

@JohnDvorak It took the 7 minutes for M.SE (and yeah, your guess was correct about hbar)

@Mr.Xcoder 05ab1e, 3 bytes (untested): .¥ß

Should work, I think that was my solution too

well means "undelta" which reverses "delta" with leading element be 0 and ß means "pop smallest and push to stack" so it should work

@LeakyNun did you see my codegolf challenge?

5:44 PM

well I prefer ß...but I seem to have rare preferences :p

Yeah true
It's interesting too see solutions in languages that don't have Undelta ಠ_ಠ

@orlp I haven't, wait

46 bytes in Python

5:47 PM
@Mr.Xcoder jelly, 5 bytes (untested): SƤṂ0«

lambda x:min(cumsum([0]+x))
from numpy import*

@Mr.Xcoder you can golf that

Actually

min(cumsum([0]+x)) -> min(cumsum(x),0)

cumsum sounds like the function out of a pornographic programmer movie

5:48 PM
Do I even need the [0]

testcase?

[0,4,5,6,7-3,4,4-2,6,-839] -> -808

I'd like to make an operation called "Reversible Delta"
like, [3, 1, 2, 0, -5, 8] -> [3, -2, 1, -2, -5, 13]
although I don't know how feasible it would be

@EriktheOutgolfer That is basically deltas([0]+list)

5:51 PM
.++Z

@Mr.Xcoder .++0
leading 0 is counted as separate 0
(pyth)
so you don't have to count on a variable such as Z being set to 0
or jelly

@Mr.Xcoder yes you need it
@EriktheOutgolfer it's a thing in 05AB1E

0;_@2\ (finally!) (oh gosh it's 7 bytes too much :( )
@LeakyNun not how I describe it though

Husk, 2 bytes: ▼∫
- Cumulative sum, - Minimum

doesn't add 0 to the list?

5:55 PM
what

oh wait it does o_o
husk cumsum is weird

It does :-)
▼:0∫ would be the version for normal languages
:P

@Mr.Xcoder Jelly, 3 bytes: +\Ṃ

invalid
jelly cumsum doesn't add 0 :p

oops

5:57 PM
@Mr.Xcoder Θ is now :0

0;<input>µ+\Ṃ
@H.PWiz Oh thanks
Actually that's redundant

@H.PWiz wait why jelly doesn't have that ಠ_ಠ

@Mr.Xcoder what are you doing

@EriktheOutgolfer, In Husk it's really :defVal so \x00 for a string and [] for a list of lists

@LeakyNun Nevermind

5:59 PM
@Mr.Xcoder Jelly, 5 bytes: 0;+\Ṃ

@H.PWiz that's just awesomely reduntant

You never know...

12 mins ago, by Erik the Outgolfer
@Mr.Xcoder jelly, 5 bytes (untested): SƤṂ0«

@LeakyNun Good, hence the Actually that's redundant, and incorrect (mine)