The Nineteenth Byte

Leaky Nun

12:20 AM

CMC: make a @xnor gate

Pavel

12:43 AM

sub{shift+shift!=1}

Adám

@LeakyNun =

Leaky Nun

@Adám language?

lirtosiast

it's Adám, what language do you think?

Anonymous

12:59 AM

Chat Mega Challenge: There are roughly 43 quintillion valid states for a 3x3x3 Rubik's Cube. What is the largest subset of valid, unsolved states that can be solved without passing through any intermediate state that is also part of that subset, using only the basic twelve moves (F, B, U, D, L, R, F', B', U', D', L', R')?

6

lirtosiast

Isn't the set just the 12 basic moves applied to the identity?

Wait

Oh you mean the

Anonymous

@lirtosiast No, because you can use multiple moves, so long as you reach the solved state without reaching any other state in the subet

lirtosiast

Lower bound: the largest of the sets of configurations whose shortest path to the identity has i moves, where 0 <= i <= 26

I'm confused, cube20.org/qtm says there is known 1 configuration requiring 26 moves and only 2 requiring 25 moves, but doesn't applying each generator to the configuration at distance 26 give you 12 such distance 25 configs?

New Main Posts

1:43 AM

-1

Q: Detecting whether we are speaking about rodents or electronic mouse

I have this task basically In this task you'll try to distinguish the meaning of words within sentences. To be more precise, you'll try to determine whether the sentence you're looking at talks about mice, the rodents, or mice, the input devices used to control a computer. I'm thinking ab...

python

Zacharý

@lirtosiast Actually, that could be any APL-type language.

@EriktheOutgolfer Depends on the question. ASCII-art: Neil. Mathematics-style-question: Dennis. Array-manipulation: Adám. Anything else, I'd say Dennis.

lirtosiast

@Zacharý True, or many others

Zacharý

APL (any variety), J, RAD, K, I'm trying to think of some more that it would fit with.

Leaky Nun

3:12 AM

CMC: output whether 4 is a prime

Anonymous

@LeakyNun 0 bytes is just about every programming language ever, using the truth machine version of truthy/falsey output

Leaky Nun

I see

xnor

4 is a pseudoprime for the Wilson's Theorem prime generator

tio.run/##K6gsycjPM/r/…

Leaky Nun

3:33 AM

:o

I totally did not see this coming

DJMcMayhem

4:04 AM

@LeakyNun Depends on the value of 4

Anonymous

It's prime for sufficiently large values of 4

Anonymous

Or sufficiently small

lirtosiast

4:30 AM

@Mego My intuition is that the number is between 10/12 N and 11/12 N where N is the size of the Rubik's cube group

Downgoat

question: do you prefer string.substring(start, end) or string.slice(start, end) or some other keyword?

Anonymous

@Downgoat [:]

Anonymous

But if it has to be a full word for a method, slice

Downgoat

@Mego oooh yes forgot I was going to do this

lirtosiast

@Downgoat are you making a language?

Downgoat

4:43 AM

yeah

does it make sense to have abs() for unsigned integers that treat it like a signed integer?

Anonymous

5:03 AM

@Downgoat abs should be an identity function for unsigned integers

user202729

@lirtosiast Or 26.

However, because 1 state can be optimally solved in reasonable time, I don't see why it is a problem. (?)

Can we prove that there exists such a set such that its complement (which contains the solved state) is connected?

lirtosiast

5:44 AM

@user202729 > The positions of the cube can be separated by a concept called permutation parity into even and odd positions. Every quarter turn from an odd position yields and even position, and vice versa, so any move sequence in the quarter-turn metric ping-pongs between even and odd positions.

Every distance 26 state must be an even permutation, so every move from it must be an odd permutation, and therefore of distance 25

Downgoat

6:03 AM

is C's >> logical or arithmetic?

@ASCII-only In VSL why is subscript parsed with an array?

Anonymous

@Downgoat logical for unsigned, unspecified for signed but most compilers do arithmetic

user202729

6:23 AM

@lirtosiast Right...

Then it's probably "up to rotation and reflection".

Yes, "and their rotations".

Downgoat

someone please explain why LLVM doesn't optimize this:

true.i.i.i:                                       ; preds = %finally2.i
  tail call fastcc void @FgNprintAstringTCString(%TCString* nonnull @1) #0
  tail call void @llvm.trap() #0

to just the trap call?

lirtosiast

6:44 AM

@user202729 The identity composed with a move is counted as 12 different positions for distance=1, so I don't think rotation answers my question

feersum

10:52 AM

I'm wondering whether I should have if statements in my "fully modular C program" sandboxed challenge

It seems hard to make interesting test programs without it

But the spec and/or the solutions might become awfully large.

New Main Posts

11:37 AM

0

Q: ASCII art H trees

An H tree is a fractal tree structure that starts with a line. In each iteration, T branches are added to all endpoints. In this challenge, you have to create an ASCII representation of every second H tree level. The first level simply contains three hyphen-minus characters: --- The next leve...

code-golf ascii-art fractal

New Main Posts

12:39 PM

0

Q: Pick out the subject, object, and predicate of a sentence

Introduction This challenge will see how simple NLP libraries of different languages have grown. Challenge This is code-golf so the shortest answer wins. Given a sentence, your program should parse it with any Natural language processing library and get the subject, predicate, and object of t...

code-golf

user202729

1:20 PM

@gnu-nobody How fast? If y>10⁹, I have no idea.

user202729

3:14 PM

I am trying to rewrite x=>(y,z)=>x.indexOf(z) without = or o for a challenge.

(y,z)=>x.indexOf(z) == (y,z)=>''.indexOf.bind(x).call(y,z) == Map.call.bind(''.indexOf.bind(x)).

I think I can do it myself.

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