The Nineteenth Byte

@lirtosiast Wait, maximum required* number of moves

Zach Gates

lol

Split personality? @LuisMendo

?

I'm considering a challenge where you are given a partially filled scrabble board, a new word (and its location), and you need to score the word

but I'm worried about it being too complex...how many of you would be interested in participating in such a challenge

12:10 AM

@lirtosiast I'm definitely interested.

It might be a good idea to create a new chat room to discuss this.

@flawr First map the reals to (0,2pi) with g(x) = 2 arccot(x). Infinity goes to 0.

@lirtosiast oooh that is interesting

Then f(x) = g^-1(2pi/3 + g(x)) = cot((2pi/3 + 2 arccot(x))/2) is a 120 degree rotation on that.

2 colors is actually easy, its the size of the diagonal

There are 2 nums a, b such that f(a) = b, f(b) = infinity, f(infinity) = a

Change the function so f(a) = a, f(b) = a instead.

I think that's your function.

12:14 AM

@lirtosiast But that's not continuous?

8

^ spotted on Facebook

hmmm, with 3 colors, you can easily construct a board that requires the maximum number of moves:

Oh yeah, I see why.

and I'm pretty sure you can repeat the pattern with more colors

I'm not sure how many moves the above board requires, though

Well, I think the last cell to be reached will be the one in the opposite corner.

12:18 AM

@DonMuesli Oh, I didn't see the continuity requirement

@El'endiaStarman not necessarily. You can spam 0,1 to reach it quicker

oh, true

Doing 1 2 0 repeatedly will finish in 12 moves.

@lirtosiast It looks to me like it might be impossible to achieve. But intuition ofteh fails in these cases :-)

@El'endiaStarman why 12?

Dennis

12:21 AM

@flawr No. f has to be bijective, therefore monotonous. If f were decreasing, f o f o f = id would be decreasing as well. Since f is increasing, if x < f(x), f(x) < (f o f)(x) and (f o f)(x) < (f o f o f)(x), so x < (f o f o f)(x). Similarly if x > f(x), x > (f o f o f)(x). Therefore, x = f(x) for all x.

bijective, therefore monotonous good point! That's the key

@Dennis +1

New Meta Posts

12:36 AM

0

Q: Why is this a duplicate?

Recently I asked this question: Solve a quadratic expression. Seconds after I posted, it was flagged as a duplicate of Resolve quadratic equation, and was downvoted several times. The two titles look similar, but, as I put in the comments, ...The main challenge for mine is interpreting a stri...

Anonymous

12:46 AM

Additionally, please do not try to argue your case for why a challenge isn't a dupe in the challenge text itself; that's what comments and meta are for. Especially do not revert an edit that removes the unneeded text. — Mego 20 secs ago

Anonymous

Is this a reasonable comment to make?

Yes.

Geobits

A bit stern, but not overly so.

Anonymous

I fear that the user might start an edit war over that unnecessary chunk

Dennis

In that case, just flag for moderator attention.

12:48 AM

@Mego Yes. We should really change the 'was flagged as dupe; please click this close button or edit your question to clarify why it isn't' message though

Kind ------- neutral -- you ----- stern (scale)

@lirtosiast That's one of the things that doesn't fit our not-a-Q&A nature.

Should one downvote a dupe?

Anonymous

You should downvote an uninteresting/low quality challenge

@CᴏɴᴏʀO'Bʀɪᴇɴ Not for being a dupe.

12:49 AM

@flawr CA.

Anonymous

The criteria for downvoting is independent of the criteria for closing, in most cases

So one should've downvoted that challenge because...?

Geobits

It is quite often that a question fits both criteria, imo.

Anonymous

Because the string parsing significantly detracts from the quality of the challenge; it's a cumbersone I/O format

Ah.

12:51 AM

I think that string parsing a quadratic equation might be interesting

Anonymous

Short version: downvote if it sucks, and close if it has major issues

especially if terms aren't combined

@Mego "Parsing a string is not interesting" isn't the objective truth

I liek that idea.

^^

12:52 AM

^

but not ^^^

There are languages in which it's fiendishly difficult (TI-BASIC)

BF

Anonymous

@NathanMerrill A combining-like-terms challenge would be interesting. Splitting a string based on a simple regex and then doing the meat of another challenge is a dupe.