The Nineteenth Byte

Mr. Xcoder

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

Erik the Outgolfer

read those...

Mr. Xcoder

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

Erik the Outgolfer

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

Mr. Xcoder

Or that

ASCII-only

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

Mr. Xcoder

4:18 PM

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

Erik the Outgolfer

jelly, 4 bytes: BSḂṆ

Mr. Xcoder

Truthy: 0, 3, 5, 6, 9, 10, ...

Falsy: 1, 2, 4, 7, 8, ...

@EriktheOutgolfer Nice

Emigna

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

Erik the Outgolfer

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

Mr. Xcoder

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

Erik the Outgolfer

4:20 PM

three

and n is 3 away from l

Mr. Xcoder

@EriktheOutgolfer 3 bytes

Wait...

Why do you need Ṇ

Like, 0 -> truthy, 1 -> falsy

Erik the Outgolfer

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

Mr. Xcoder

Oh ok then

Erik the Outgolfer

btw an alternative would be BS2ḍ

or even BḊSḂ I guess

Mr. Xcoder

8 bytes in Pyth... Ugh

Seems too long maybe?

Erik the Outgolfer

4:24 PM

!%sjQ2 2 right?

Mr. Xcoder

!%sjQK2K or !%sjQ2 2

Yeah

Added that fancy explanation for something obvious :-/

orlp

@Emigna why not?

Lynn

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

yay!

Mr. Xcoder

@Lynn Woah nice!

Emigna

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

Lynn

4:27 PM

I still think some arithmagical nonsense is gonna turn out to be shorter.

Erik the Outgolfer

like, outgolf xnor? :D

John Dvorak

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

Alex K Chen

@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...

ASCII-only

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

Mr. Xcoder

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

ASCII-only

4:31 PM

@AlexKChen bloatware is in all windows computers...

Mr. Xcoder

@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.

AdmBorkBork

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

12

ASCII-only

@Mr.Xcoder yes, too many

Alex K Chen

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

Mr. Xcoder

Then takes its bitwise complement and mods by 2

ASCII-only

4:32 PM

@Mr.Xcoder right

Lynn

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

Mr. Xcoder

@Lynn Oh yeah you're right

Lynn

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 …

ASCII-only

@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

Lynn

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

ASCII-only

4:34 PM

I was thinking of using differences, but can't find a pattern

Mr. Xcoder

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

ASCII-only

The 2s?

Lynn

The differences aren’t very useful

Mr. Xcoder

I don't think that's relevant though

ASCII-only

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

Oh well

Mr. Xcoder

4:36 PM

Yeah, will never be golfier than the arithmagical nonsense -- Lynn

ASCII-only

@Mr.Xcoder what.

Mr. Xcoder

nvm

ASCII-only

There's kinda a pattern but not really tio.run/…

It appears to be a self similar sequence actually tio.run/…

Erik the Outgolfer

yes it is I discovered it too

ASCII-only

But we only have 10 bytes left so not enough

Erik the Outgolfer

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

Alex K Chen

no

Erik the Outgolfer

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

Lynn

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

ASCII-only

Oh so Arnauld's already mentioned it

Lynn

several users have said some things about it in the thread

Alex K Chen

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

Erik the Outgolfer

huh?

Alex K Chen

37 seconds.

If you think this is too hard on literary criticism, read the Wikipedia article on deconstruction.

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

AdmBorkBork

@EriktheOutgolfer Binary solo!

ASCII-only

@AlexKChen you sound like a markov bot

Erik the Outgolfer

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

the argument is iteration

AdmBorkBork

4:52 PM

@EriktheOutgolfer From a Flight of the Conchords skit

ASCII-only

5:08 PM

Actually

John Dvorak

@AlexKChen you deserve a second try

ASCII-only

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

John Dvorak

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

Alex K Chen

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

John Dvorak

:@alex I'll enjoy watching that: P

Mr. Xcoder

5:11 PM

CMC: Given two positive integers X and Y, return (X * (2 ** Y)) - 1.

Where ** means power.

Erik the Outgolfer

jelly, 3 bytes: æ«’

Mr. Xcoder

17 in Python

Pavel

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

Mr. Xcoder

@Pavel x=>y=>x<<y-1

I think?

Pavel

IDK.

Mr. Xcoder

5:13 PM

5, 8 -> 640

Erik the Outgolfer

pyth, 4 bytes (takes as list): t.<F

or one that takes in reverse order: t.<E

Mr. Xcoder

What!??!

Pavel

@Mr.Xcoder Works, thanks

Actually no

Mr. Xcoder

No

I am wrong?

Pavel

I confuse

@Mr.Xcoder Try it with 5, 8

Mr. Xcoder

5:14 PM

1279 is correct

Erik the Outgolfer

and 05ab1e doesn't have shifts

Alex K Chen

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

Pavel

Oh ok

._.

John Dvorak

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

Mr. Xcoder

5, 8 -> 1279

Alex K Chen

5:15 PM

hmm... I gotta try it on MSE chat after dinner.

stay tuned for the fun.

Mr. Xcoder

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

Any idea?

Erik the Outgolfer

@Mr.Xcoder dunno js

Mr. Xcoder

@EriktheOutgolfer In Python

Erik the Outgolfer

05ab1e, 3 bytes: so*

John Dvorak

@AlexKChen toss me the link then

Mr. Xcoder

5:16 PM

Try it online! and Try it (:O) online!

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

Erik the Outgolfer

@Mr.Xcoder doesn't?

HyperNeutrino

tutorialspoint.com/python/operators_precedence_example.htm

Erik the Outgolfer

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

Pavel

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

Mr. Xcoder

@EriktheOutgolfer It doesn't

HyperNeutrino

5:17 PM

I didn't use Python's OOP

I think

Mr. Xcoder

1 min ago, by Mr. Xcoder

Try it online! and Try it (:O) online!

HyperNeutrino

also sorta surprised that people remember proton exists lol

Pavel

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

Erik the Outgolfer

@Mr.Xcoder wait a sec

Leaky Nun

hi everyone

John Dvorak

5:18 PM

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

Mr. Xcoder

hi @LeakyNun

Erik the Outgolfer

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

Pavel

Hello @LeakyNun

Mr. Xcoder

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

John Dvorak

Precedence

Mr. Xcoder

5:20 PM

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

Leaky Nun

@Mr.Xcoder - has higher precedence

Erik the Outgolfer

but

Leaky Nun

sniped

Erik the Outgolfer

wait

Mr. Xcoder

@LeakyNun Not according to Python wiki

Erik the Outgolfer

5:20 PM

actually - has higher precedence lol

Leaky Nun

- precedence over <<

@Mr.Xcoder link?

Erik the Outgolfer

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

Mr. Xcoder

oh we have read them in reverse order

Erik the Outgolfer

so yes - is over <<

Pavel

<-- is very confused by the ongoing discussion

Mr. Xcoder

5:21 PM

5 mins ago, by Mr. Xcoder

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

Leaky Nun

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

Mr. Xcoder

lol

Pavel

@HyperNeutrino Did you use any OOP?

HyperNeutrino

yes

check proton_parser.py

Pavel

I thought you mean in the syntax of the language

Erik the Outgolfer

5:22 PM

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

Pavel

Not in the code for the implementation

Erik the Outgolfer

although in python that's not the case

Mr. Xcoder

me too

orlp

@EriktheOutgolfer in which language is it the case?

Mr. Xcoder

@orlp none it seems

Leaky Nun

5:22 PM

@EriktheOutgolfer bitwise is low level

low level = low precedence

Erik the Outgolfer

I don't think exactly like that

Leaky Nun

then why does ** take precedence over *?

orlp

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

Erik the Outgolfer

@LeakyNun heh

I guess to follow pemdas

Leaky Nun

@EriktheOutgolfer then why is it the case in pemdas?

Erik the Outgolfer

5:24 PM

don't ask me, ask who made pemdas

Leaky Nun

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

orlp

@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

Mr. Xcoder

@LeakyNun Nice! What is it like there?

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

maybe?

Untested.

Leaky Nun

@orlp I thought you live in london

Erik the Outgolfer

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

Mr. Xcoder

5:26 PM

Incorrectly.

orlp

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

Leaky Nun

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

orlp

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

Mr. Xcoder

Pls people delete this!

orlp

I was referring to the north sea :)

Leaky Nun

5:28 PM

@orlp oh lol

@Mr.Xcoder done

Mr. Xcoder

Thanks!

Erik the Outgolfer

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

Mr. Xcoder

@EriktheOutgolfer You are missing the f

Erik the Outgolfer

then I'll have to make it anew

Mr. Xcoder

And orlp is missing an i :P

orlp

5:31 PM

@Mr.Xcoder shhh

Leaky Nun

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

orlp

:D

Leaky Nun

just a guess

probably wrong

Erik the Outgolfer

I think that's wrong

Leaky Nun

sure

it's just off the top of my head

Erik the Outgolfer

5:32 PM

I think >> has higher priority than ^

Mr. Xcoder

Incorrect

orlp

@LeakyNun wrong

Leaky Nun

lol I won't search online

but then I would never get the answer

orlp

to be honest the whole point of this challenge is to show that it's silly

I think certain things should be forced parenthesized

Erik the Outgolfer

is this correct?

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

Alex K Chen

5:34 PM

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

orlp

@EriktheOutgolfer appears to be

Mr. Xcoder

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

God damn Erik

Well mine is different and works

Erik the Outgolfer

@Mr.Xcoder & > ^

Mr. Xcoder

Try it online!

orlp

@Mr.Xcoder but not fully parenthesized

Mr. Xcoder

5:37 PM

@orlp Good now?

orlp

@Mr.Xcoder c*d+e

Erik the Outgolfer

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

orlp

what is this?

Erik the Outgolfer

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

Mr. Xcoder

ಠ__________________________________ಠ

orlp

5:39 PM

@Mr.Xcoder it doesn't though

Mr. Xcoder

@EriktheOutgolfer @orlp Both are incorrect

Not just mine, Erik's is too

orlp

oops

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

????

Leaky Nun

@orlp will you be going to the UK anytime?

orlp

@LeakyNun perhaps

Erik the Outgolfer

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

ah leaky ninja probably

orlp

5:41 PM

but anyway I don't really care :D

Erik the Outgolfer

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

orlp

my entire point was that it's stupid

there shouldn't be precedence rules for stuff like this

Erik the Outgolfer

agree

orlp

just left to right

Mr. Xcoder

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

Erik the Outgolfer

5:42 PM

@orlp or just force parentheses

or prefix/polish notation (please don't :p)

Alex K Chen

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

Erik the Outgolfer

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

Mr. Xcoder

Should work, I think that was my solution too

Erik the Outgolfer

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

orlp

@LeakyNun did you see my codegolf challenge?

Mr. Xcoder

5:44 PM

@EriktheOutgolfer Actually I had .¥W

Erik the Outgolfer

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

Mr. Xcoder

Yeah true

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

Erik the Outgolfer

because in jelly I also prefer ȧ instead of a, ȯ instead of o, ⁼ instead of =, ⁻ instead of n

Leaky Nun

@orlp I haven't, wait

Mr. Xcoder

46 bytes in Python

Erik the Outgolfer

5:47 PM

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

Mr. Xcoder

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

Erik the Outgolfer

@Mr.Xcoder you can golf that

Mr. Xcoder

Actually

Erik the Outgolfer

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

orlp

cumsum sounds like the function out of a pornographic programmer movie

Mr. Xcoder

5:48 PM

Do I even need the [0]

:o ninja'd badly

Leaky Nun

testcase?

Mr. Xcoder

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

Erik the Outgolfer

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

Mr. Xcoder

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

Erik the Outgolfer

yes

Mr. Xcoder

5:51 PM

.++Z

Erik the Outgolfer

@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

Leaky Nun

@Mr.Xcoder yes you need it

@EriktheOutgolfer it's a thing in 05AB1E

Erik the Outgolfer

0;_@2\ (finally!) (oh gosh it's 7 bytes too much :( )

@LeakyNun not how I describe it though

Mr. Xcoder

Husk, 2 bytes: ▼∫

∫ - Cumulative sum, ▼ - Minimum

Erik the Outgolfer

doesn't add 0 to the list?

Leaky Nun

5:55 PM

what

Erik the Outgolfer

oh wait it does o_o

husk cumsum is weird

Mr. Xcoder

It does :-)

▼:0∫ would be the version for normal languages

:P

Leaky Nun

@Mr.Xcoder Jelly, 3 bytes: +\Ṃ

Erik the Outgolfer

invalid

jelly cumsum doesn't add 0 :p

Leaky Nun

oops

H.PWiz

5:57 PM

@Mr.Xcoder Θ is now :0

Mr. Xcoder

0;<input>µ+\Ṃ

@H.PWiz Oh thanks

Actually that's redundant

Erik the Outgolfer

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

Leaky Nun

@Mr.Xcoder what are you doing

H.PWiz

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

Mr. Xcoder

@LeakyNun Nevermind

Leaky Nun

5:59 PM

@Mr.Xcoder Jelly, 5 bytes: 0;+\Ṃ

Erik the Outgolfer

@H.PWiz that's just awesomely reduntant

H.PWiz

You never know...

Erik the Outgolfer

12 mins ago, by Erik the Outgolfer

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

Mr. Xcoder

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

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