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What is the Sandbox?

This "Sandbox" is a place where Code Golf users can get feedback on prospective challenges they wish to post to the main page. This is useful because writing a clear and fully specified challenge on the first try can be difficult. There is a much better chance of your challenge being well received if you post it in the Sandbox first.

To post to the Sandbox, scroll to the bottom of this page or click on the "Add Proposal" link below, and click "Answer This Question". Click "OK" when it asks if you really want to add another answer. Write your challenge just as you would when actually posting it. You may also add some notes about specific things you would like to clarify before posting it. Other users will help you improve your challenge by rating and discussing it. When you think your challenge is ready for the public, go ahead and post it, replace the post here with a link to the challenge and delete it.

See the Sandbox FAQ for more information on how to use the Sandbox.

The Sandbox works best if you sort posts by "active".

Add Proposal

Search the Sandbox

Browse your pending proposals

Get the Sandbox Viewer to view the sandbox more easily

To add an inline tag to a proposal use shortcut link syntax with a prefix: [tag:king-of-the-hill]

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2970 Answers 2970

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Randomly produce a (name of a language) source file that is possibly a quine

Write code in any language that randomly generate a (name of a language) (Java?) source file, meeting the two criteria:

  • It must always (with probability 1) compile successfully in a (language) compiler and version of your choice.
  • It must have non-zero probability to be a quine in (language).

You don't have to make it able to generate all possible programs, and the probability doesn't have to be uniform. The objective is to write a generator shorter than the shortest possible quine in (language) compressed. Technically your code could be deterministic and generate only one program, that is a quine. But it isn't supposed to be competitive.

Your code must not have the potential to damage the computer. But it doesn't matter what the generated (language) program does when it is not the quine that qualifies your answer.

(Restrictions about compiler flags to be added.)

You could either use the built-in random functions and assume they generate true random numbers, or request random information from the input (details to be added). Your code only need to have probability 1 to terminate.

Shortest code wins.


Possible rule

You may not call any (language) compiler or anything else that could check (language) syntax.


I was thinking about C++, but there are short patterns to execute any binary machine code. The language should also have a verbose structure, and not a too short quine.

Candidates: Java, Haskell, Shakespeare Programming Language, Mornington Crescent, SQL, ferNANDo.

Or: Generate a PNG file that is possibly this image. But that may depend to much on a PNG library, and the other part is trivial.

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  • \$\begingroup\$ @trichoplax The objective is to write a generator (in any language) shorter than the shortest possible quine (in a specific target language) compressed. \$\endgroup\$ – jimmy23013 May 26 '19 at 8:26
  • \$\begingroup\$ @trichoplax Yes, unless we argue about the case that is possible but has probability 0 to not terminate. \$\endgroup\$ – jimmy23013 May 26 '19 at 8:58
  • \$\begingroup\$ Do I understand it correctly that we can print a normal-ish quine, but with all its strings replaced with random strings without quotes, newlines and other offending characters? \$\endgroup\$ – the default. May 26 '19 at 9:15
  • \$\begingroup\$ As of currently, yes. I hope there are better solutions, but I'm worrying about that this is actually the best solution, and makes it trivial. \$\endgroup\$ – jimmy23013 May 26 '19 at 9:18
  • \$\begingroup\$ Is it possible to somehow restrict a Java program from destroying the computer with a finite amount of code? If so, generating all strings, trying to compile them and running them parallelly until any happens to be a quine might or might not be even shorter. \$\endgroup\$ – the default. May 26 '19 at 9:22
  • \$\begingroup\$ @someone The generator should not destroy the computer. But as of currently it doesn't disallow trying all strings. Maybe I'll forbid calling the Java compiler or syntax checker. \$\endgroup\$ – jimmy23013 May 26 '19 at 9:29
  • \$\begingroup\$ Curiously, this seems similar in concept to Solve Subset-Sum in polynomial time (…if P = NP). \$\endgroup\$ – xnor May 27 '19 at 2:38
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    \$\begingroup\$ I'm actually having trouble imagining how to beat a hardcoded quine. Generating nontrivial valid code seems hard. Maybe I'm missing something. \$\endgroup\$ – xnor May 27 '19 at 2:43
  • \$\begingroup\$ @xnor I think hardcoding a quine except for a string is most likely going to win. So I'm looking for a language that potentially allows more approaches. I may also change it to generate a program for a task other than quine. \$\endgroup\$ – jimmy23013 May 27 '19 at 2:54
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Finding distinct road sections

I was recently working on a grid-based road procedural generator, and thought of a neat idea for a new challenge:

The Task

Given a square (equal width and height) 2d array in which each item is one of 2 distinct values (of your choice): grass and road (I will use _ and # in examples), output the grid modified such that each distinct segment of road tiles has had its values changed to a unique value.

Two road tiles are considered to be part of the same segment if they neighbor each other in at least 1 cardinal directions.
Diagonal neighbors are not considered to be part of the same segment (unless they are connected cardinally elsewhere)
A single road tile with no connections is considered to be its own distinct segment.

You may choose the 2 input values used, and all output values used.
"Grass" tiles must remain unchanged.

You may assume there will always be at least 1 road segment, and that the array dimensions will be no larger than 64 by 64

Example:

Input:

___#__######____
_###__#_#_______
___#_##_########
___#____________
####_#######__##
_#_#_#__________
_#_#_#______####
___#_#__________
##_#_##_________
______#_________
_______#_#######
______##________
__###_#_______##
_##_____________
__#######_______
__#_____________

_ is "grass" and # is "road"

Output:

___3__111111____
_333__1_1_______
___3_11_11111111
___3____________
3333_4444444__22
_3_3_4__________
_3_3_4______5555
___3_4__________
66_3_44_________
______4_________
_______7_8888888
______77________
__000_7_______99
_00_____________
__0000000_______
__0_____________

Scoring

This is so fewest bytes in each language wins

Test cases

TBA

Sandbox

  • I feel like the task is poorly worded, but can't think of a better way to word it.
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  • \$\begingroup\$ This seems really familiar, but I can't seem to find a dupe... \$\endgroup\$ – AdmBorkBork May 30 '19 at 19:55
  • \$\begingroup\$ I'm worried about the numbering - is there a defined numbering scheme? The way you have it, it starts from the bottom left and reads to top right. But most (read: ALL) programming languages read from top left to bottom right. \$\endgroup\$ – mackycheese21 Jun 6 '19 at 1:14
  • \$\begingroup\$ I would specify either the numbering relation, or that it doesn't matter. \$\endgroup\$ – mackycheese21 Jun 6 '19 at 1:14
  • \$\begingroup\$ @mackycheese21 You may choose the 2 input values used, and all output values used. \$\endgroup\$ – Skidsdev Jun 6 '19 at 2:10
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Draw a regular prism

Input

The input is a single integer i between 3 and 8.

Output

The image of a regular prism with the two regular polygonal faces having i edges each. For example, if i=3 your code should draw a triangular prism using two equilateral triangles.

Rules

The diameter of the polygonal (i.e. triangular if i=3) faces must be at least 200 pixels as should the distance between the regular faces. You can show the image at any angle you like as long as at least two faces of the prism are visible, including one of the two regular polygonal faces.

The edges of the prism that are visible should be in black and the edges that are not visible should be drawn with dotted black lines, a dotted line being a line where in at least 3 distinct, non-connected places (meaning separated by black) there's an absence of black color.

Examples

enter image description here

enter image description here

enter image description here

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  • \$\begingroup\$ You have your examples with the bases aligned. Is that required for output? \$\endgroup\$ – AdmBorkBork May 30 '19 at 19:35
  • \$\begingroup\$ @AdmBorkBork No. Unless you think it should be? \$\endgroup\$ – user9207 May 30 '19 at 20:29
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Is this a valid Irish word?

In Irish, most consonants are divided into broad (velarized) and slender (palatalized) variants, and the orthography marks them with neighboring vowels, which are similarly divided. This gives rise to the caol le caol agus leathan le leathan (slender with slender and broad with broad) rule – a medial sequence of consonants must have the same class of vowel on either side: in leabhar, bh is surrounded by two broad consonants, so it is broad as well, and in cailín, l is surrounded by two slender consonants, so it is slender. a, o and u are broad and e and i are slender (similar with the vowels with the fada: á ó ú é í); ae is also considered broad.

Given a word, output whether it follows this rule.

Input

You may assume that the input has only the following characters and their uppercase variants:

aábcdeéfghiílmnoóprstuú

Tests

Valid:

deartháireacha
madra
nuachtán
gaolta
ceannasaithe
snámhann
fómhair
laethanta
béar
Bealtaine
hAoine

Invalid:

codegolf
delta
alishanoi
ABI
anseo
breithlá

(Note that anseo and breithlá are Irish words, but they happen not to follow this rule. You should still output a falsy answer for them for the sake of simplicity.)

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    \$\begingroup\$ Jebus, I haven't heard "slender with slender and broad with broad" in a couple of decades, that gave me a flashback! You note that "anseo" ("here", for the benefit of the non-Gaeilgeoirí) doesn't follow the rule but you should probably specify the expected output for it - I'd suggest against special-casing it and having it be invalid. \$\endgroup\$ – Shaggy Jun 2 '19 at 19:51
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    \$\begingroup\$ This needs a much better definition of what is a broad consonant versus what is a slender consonant, unless I'm not understanding the challenge. \$\endgroup\$ – AdmBorkBork Jun 3 '19 at 12:56
  • \$\begingroup\$ @AdmBorkBork as I understood it, broad and slender consonants are indistinguishable in writing, the point is to detect consonants that would have to be both at the same time. \$\endgroup\$ – FrownyFrog Jun 13 '19 at 4:49
  • \$\begingroup\$ I'd suggest listing their uppercase variants \$\endgroup\$ – l4m2 Jun 25 '19 at 15:52
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Moved to Make Gimbap cutter

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  • \$\begingroup\$ I don't understand how your last test case follows your rules (and other test cases), since I only see two valid Gimbap, @) and @))) in the input. \$\endgroup\$ – AdmBorkBork Jun 7 '19 at 12:55
  • \$\begingroup\$ @AdmBorkBork There is two valid Gimbap, @) and @))), than split them to @) and @) @) @). So output is @) @) @) @). I'm not that good at English, though. Can you suggest me the way to make question clearer? \$\endgroup\$ – LegenDUST Jun 7 '19 at 13:01
  • \$\begingroup\$ Oh, so the output is only the valid Gimbap? That makes more sense. Will the input ever contain anything other than @ or )? I would recommend it doesn't. \$\endgroup\$ – AdmBorkBork Jun 7 '19 at 13:04
  • \$\begingroup\$ @AdmBorkBork Input is made with only @ and ). \$\endgroup\$ – LegenDUST Jun 7 '19 at 13:06
  • \$\begingroup\$ Would )))@) be a valid input? \$\endgroup\$ – Luis felipe De jesus Munoz Jun 7 '19 at 20:43
  • \$\begingroup\$ @LuisfelipeDejesusMunoz It would. Then output will be @). I'll add that to example. \$\endgroup\$ – LegenDUST Jun 8 '19 at 4:14
  • \$\begingroup\$ So in other words: count all )s which occur after the first @ and output that many @) separated by spaces? \$\endgroup\$ – Peter Taylor Jun 12 '19 at 13:51
  • \$\begingroup\$ @PeterTaylor Yup. But I moved it into main site. \$\endgroup\$ – LegenDUST Jun 12 '19 at 13:56
  • \$\begingroup\$ When you do that you should edit the sandbox post to just be a link to the question on the main site, and then delete it, as described in the second paragraph at the top of this page. \$\endgroup\$ – Peter Taylor Jun 12 '19 at 14:11
  • \$\begingroup\$ @PeterTaylor Thanks you. I'll edit my posts. \$\endgroup\$ – LegenDUST Jun 13 '19 at 5:37
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Draw an Image on the screen efficiently

Imagine you have a special rectangular screen made of square pixels. It consists of \$n\$ rows and \$m\$ columns. For every row and every column there is one swich (so \$n + m\$ switches in total). To turn a certain pixel on - let's say at position \$(i,j)\$ - we can press switch \$i\$ (of the row switches) and switch \$j\$ (of the column switches) at the same time.

As soon as some pixel has been turned on, it stays on, even if we press the same combination of switches again. META: Is this a good idea? Or should we say that each pixel should be turned on exactly once and may not be activated again?

But we can also press an arbitrary number of switches at the same time: Lets say we press switches \$0,2,3\$ of the row switches and \$1,5\$ of the column switches, then all the pixels \$(i,j)\$ with \$i \in \{0,2,3\}\$ and \$j \in \{1,5\}\$ will get turned on, so all the pixels \$(0,1),(0,5),(2,1),(2,5),(3,1),(3,5)\$.

If we now want to draw a picture on the screen you could do that pixel for pixel, and we'd need \$n \cdot m\$ actions in the worst case - that is, when we have to turn on every pixel. But as we can press an arbitrary number of switches at the same time, we can do better than that. We can for example do row by row: This means we select one switch for the current row, and all necessary column switches to activate all the pixels we need for this row, so in total we would need \$\min\{n,m\}\$ actions. But can we do better than that?

The task is now to write a program that given some black and white image computes a shortest sequence of actions (=simultaneous switch activations) that turns on exactly all the white pixels of the given image.

Details

  • You can also take a matrix/list of lists as input, or a list of the coordinates of the active pixels.
  • You can additionally take the size \$(n,m)\$ as an input (or \$(n-1,m-1)\$ if you prefer.
  • The output is also flexible: You can represent every action as a list of two lists with the corresponding indices of the switches where each of the indices are in \$\{0,1,\ldots,n-1\}\$ or \$\{0,1,\ldots,m-1\}\$ respectively (or also 1-based indexing is fine), or alternatively you enumreate all switches as \$\{0,1,2,\ldots,n+m-1\}\$ and use just one list to represent this action.

    Alternatively you can also just use lists of size \$n\$ and \$m\$ (or one of size \$m+n\$) with truthy and falsey values representing the switches that get activated.

Related: Matrices Generated Using Rectangles

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    \$\begingroup\$ It may be worth clarifying that the switches don't stay on after an action (i.e. we don't spend actions deactivating them). I'm not sure if it was the use of the word "switch" over "button" that made me think this would be the case but it may be worth running it past some other people. \$\endgroup\$ – FryAmTheEggman Jun 4 '19 at 19:07
  • \$\begingroup\$ @FryAmTheEggman Thanks a lot for the effort of going through this draft! Is "button" used more for switched that just make a momentary contact? To be honest the alternative challenge that include also switching off the switches would maybe be even more interesting! \$\endgroup\$ – flawr Jun 4 '19 at 19:19
  • \$\begingroup\$ There are probably quite a few variations of this that would be fun (I'm still thinking about your meta question)! In any case, where I live I think that is the case in that most people would say my laptop has a power button, but the room I'm in has lights controlled by a switch. \$\endgroup\$ – FryAmTheEggman Jun 4 '19 at 19:27
  • \$\begingroup\$ Maybe add restricted-complexity, if this is even possible in polynomial time? \$\endgroup\$ – lirtosiast Jun 16 '19 at 8:05
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Cumbersome IO format

The cops' task is to write a program in language A to solve (task about integer lists 1) and a program in language B to solve (task about integer lists 2). The second program must be able to use the output of the first program.

Others could golf your programs. Highest (C + total length of your programs) / (C + minimum total length of the programs without the restriction) wins. (C is a fixed constant to be chosen.)

(Details to be written. The format would be similar to The Bowlers-Golfers Fraction War. Minimum lengths of the two parts would be taken from other challenges.)

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  • \$\begingroup\$ Would a pair of languages that both implicitly eval input and uneval output (and since it's a integer list, pretty much all golfing languages I know of work like that for lists) work as a optimal (besides the program itself) solution? What does "program length" in the score formula stand for? The score seems to always be 1 to me. \$\endgroup\$ – the default. Jun 13 '19 at 15:17
  • \$\begingroup\$ @someone Highest score wins. This is a bowling challenge to find two languages which work the worst with the other one's IO format. But I think this may not work well, as there isn't much to do after you finds the languages. \$\endgroup\$ – jimmy23013 Jun 13 '19 at 16:40
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Moved here

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    \$\begingroup\$ It would be good to include the words "diameter" and "graph". I don't think this particular graph statistic has been the subject of a question before, but it could well come up again in the future and then those search terms would make it easier to use this as a dupe target. \$\endgroup\$ – Peter Taylor Jun 19 '19 at 11:53
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Digit Sum of Sum of Digit Sums

Input: An integer from 1 to 1000 (known as N) Expected behavior: The code will go through the first N integers, and work out the digit sum for each integer, the code will then take these digit sums and add these together. The code will then take this total and work out the digit sum for that number. The final number is the expected output.

Example 1:

Input: 12

Output: 6

Behavior:

1) Numbers
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12
2) Digit Sums
1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3
3) Sum of Digit Sums
51
4) Digit Sum of Sum of Digit Sums
6

Example 2:

Input: 20

Output: 3

Behavior:

1) Numbers
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20
2) Digit Sums
1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 2
3) Sum of Digit Sums
102
4) Digit Sum of Sum of Digit Sums
3

There are no restrictions on language type as long as the standard loopholes are avoided. Please demonstrate your code using the last three digits of your current reputation score.

This is code-golf, the shortest number of characters in code will be deemed the winner. In the event of a tie, the one with highest popular answer will be crowned the winner. If both answers are tied in terms of popularity and size, a fight to the death will be used to declare the winner (just kidding...)

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    \$\begingroup\$ Why would anyone want to do this? Motivation is part of a good question. \$\endgroup\$ – Peter Taylor Jun 20 '19 at 8:01
1
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Gitify a graph

Given a undirected connected graph, create a git repository with a commit graph that is isomorphic to the input graph.

META:

  • This is just a rough idea: I first should think about what kind of graphs can actually be represented in a git repository. (the input format could be flexible: take an adjacency matrix or e.g. a list of edges or maybe some native graph structure)
  • another idea would be following: given some \$n =1,2,3,\ldots\$ create complete graph of \$n\$ nodes
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  • \$\begingroup\$ Should adjecency read adjacency? \$\endgroup\$ – Jonathan Frech Jun 19 '19 at 22:38
  • \$\begingroup\$ @JonathanFrech yes, thanks a lot! \$\endgroup\$ – flawr Jun 20 '19 at 12:33
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Introduction

When dealing with data in two dimensions, data scientists looove to see straight lines emerge, as they can use a simple linear regression to model it - meaning we assume it is in the form of y=mx+b, and all that's left is to find the best m and b to describe the data.

There are several ways to fit a line to any data (I saw there was a challenge with Ordinary Least Squares once), however one of the most flexible one is gradient descent.

When given vectors X and Y, we start with an initial guess of m and b, then iteratively update them, and hopefully we get a better fit when we're done.

We give a "grade" to our current fitted line with mse (the lower the grade - the better the fit):

loss = mean((y - (m * x + b)) ** 2 for x, y in zip(X, Y))

And in each iteration we change m and b using the gradient of that same grade:

b -= 2 * alpha * mean((m * x + b) - y for x, y in zip(X, Y))
m -= 2 * alpha * mean(((m * x + b) - y) * x for x, y in zip(X, Y))

Here alpha is the learning rate (usually smaller than 1), used to keep the steps small enough to advance towards the minimum grade, rather than overstepping it.

The last question asked is when should we stop these iterations. We (a bit arbitrarily) impose two conditions:

  1. The absolute relative change in the grade between two iterations abs(grade1 - grade2)/grade1 is changed by less than some given epsilon, and/or
  2. A given number of iterations N has been performed already.

p.s. I started by assuming the data is just y(x), however this method may be easily extended to an arbitrary number of free variables and one dependent variable.

Challenge

Write a program that accepts inputs: X, Y, m, b, epsilon, N and returns the updated m and updated b after performing gradient descent as described.

corner cases:

  • X and Y may be empty, in which case m and b are returned unchanged.

This is code golf, so shortest code in bytes wins.

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  • \$\begingroup\$ This is in need of a woked example and a fee test cases. \$\endgroup\$ – Shaggy Jun 22 '19 at 22:17
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    \$\begingroup\$ What does mean mean? What does zip mean? Those should be made clear, just like you made alpha clear. \$\endgroup\$ – AdmBorkBork Jun 25 '19 at 12:44
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Proposed alternative to this

Golf an H interpreter

H is a text-based, weakly-typed string concatenation language. You task is to run an H script. You may do so by creating an interpreter, a compiler, a transpiler, or by any other reasonable means.

Definitions

Anything not defined herein is undefined behaviour and your implementation does neither have to support it nor does it need to throw an error. This includes unmatched quotes, invalid escapes, usage of variables before definition, etc. All given H scripts will abide by all the rules as stated.

General H syntax

Scripts: One or more lines, each containing zero or more statements, optionally followed by a comment.

White-space: you only have to support spaces in strings (tabs are escaped), plus tabs and/or spaces leading up to a comment.

Operators: There's only one, +, which is string concatenation.

Comments begin with # and continue until the end of the line. # may be prefixed by one or more spaces and/or tabs.

name: a sequence of exactly 4 single-case ASCII letters [A-Z] or [a-z] (you decide the scheme)

value: a +-delimited sequence of one or more strings (see below) and/or previously defined names. The combined value will never exceed 1000 characters.

Strings

Opened and closed by " and support ASCII 32–126 but with the following escape sequences:

\\: the literal backslash character; \

\n: a line break; CR, LF, CRLF, or LFCR (you decide)

\": a quotes symbol; "

\t: a tab character; (HT) or 2, 4, or 8 spaces (you decide)

A string matching the regex 0|-?[1-9]\d?\d? (i.e. look like an integer) may be left unquoted.

Statements

Terminated by ; but may not span multiple lines. There are only three types of H statements:

def name=value; sets the variable name to the given value.

print(value); prints value without trailing line break.

input(value;name); prints value without trailing line break, allows the user to enter a sequence of characters that extend that line, and assigns the characters to name. Any subsequent output begins on the next line.

Test script

The following assumes you have decided on the uppercase variable name scheme:

def HELO="Hello, ";
def HSMO=HELO+"strange"+-1;print("");
input(HSMO+"what is your name?";NAME);         #enter "User A" via stdin
#print(-123)   # nope
print(HELO+"\""+NAME+"\"\n\tthis isn't APL\\"+360+"!");

#done
print(-12+34)	# note the tab before #

Here is the equivalent using a lowercase variable name scheme:

def helo="Hello, ";
def hsmo=helo+"strange"+-1;print("");
input(hsmo+"what is your name?";name);         #enter "User A" via stdin
#print(-123)   # nope
print(helo+"\""+name+"\"\n\tthis isn't APL\\"+360+"!");

#done
print(-12+34)	# note the tab before #

Running the appropriate script, and entering User A should, according to the scheme where \t means ASCII 9 (HT), leave the console/screen/window showing:

Hello, strange-1what is your name?User A
Hello, "User A"
	this isn't APL\360!-1234

If instead you decided that \t means four spaces, it should show:

Hello, strange-1what is your name?User A
Hello, "User A"
    this isn't APL\360!-1234

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  • 1
    \$\begingroup\$ You may want to explicitly state that User A is the STDIN-input in the Test script. I must admit I just can't read and read past the explanation of input(value;name); when going through the test script and was thinking: where is def name="User A";. And based on "Anything not defined herein is undefined behaviour and your implementation does neither have to support it nor does it need to throw an error." we can assume all scripts are valid, so no " that are unmatched, and no variable used before it is defined, and stuff like that? \$\endgroup\$ – Kevin Cruijssen Jun 28 '19 at 13:45
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    \$\begingroup\$ @KevinCruijssen How is it now? \$\endgroup\$ – Adám Jun 28 '19 at 15:50
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    \$\begingroup\$ Perfect. :) I had already upvoted I see. Everything is clear to me now. \$\endgroup\$ – Kevin Cruijssen Jun 28 '19 at 16:40
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    \$\begingroup\$ @UserA No. There is an overwhelming consensus that one should avoid bonuses in code golf. \$\endgroup\$ – Adám Jul 3 '19 at 13:23
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    \$\begingroup\$ @UserA It is very probably that many of the solutions will allow all of those any way. \$\endgroup\$ – Adám Jul 3 '19 at 13:24
1
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Phases of the Clock Moon Numbers

We can imagine all the factors of a number. For example 7 has factors 1 and 7. 12 has factors 1, 2, 3, 4, 6, and 12. 9 has factors 1, 3, and 9.

We can also imagine that a number has a position on the edge of a wheel or circular face. Let us divide our circle into 12 pieces around the edge evenly. In fact, we can call this a clock face. Human culture has settled on most clock faces having 12 numbers.

Therefore, we can imagine creating hands on a clock face for an integer that we have been given, like 7. Each hand can be imagined as a nice, easily visible line drawn from the center of the circle to the position of the number on the edge of the circle. We can also imagine creating hands on the face for all of that integer's factors, like 1 and 7. Now, we can imagine the clock face with hands at each factor. 1 and 7 for 7. This clock face now has 2 hands.

The number 9 will have 3 hands, at 1, 3, and 9.

The number 10 will have 4 hands, at 1, 2, 5, and 10.

The number 12 will have 5 hands, at 1,2,3,6, and 12.

The number 13... er... well, in that case, we use modular arithmetic. The number 12 becomes 1. In mathematical language, we might say the number 13 modulo 12 is 1. Another way to say this is that the remainder of 13 divided by 12 is 1. We could also say that 13 is congruent to 1, modulo 12.

At any rate, our imaginary clock face for the number 13 will have hands at 1 and.... 1. Now, we will say that the two hands are redundant, so it actually only has one hand, pointing to the position 1.

The number 14 will have 4 hands, at 1, 2, 7, and... 2. So actually just three hands.

Now, you may notice a pattern here. Some numbers generate a clock face with hands clustered together around the right hand side of the face, like 6 with 1, 2, 3. Other numbers seem to have hands all over the face, spread more evenly, like 20 with 1, 2, 4, 5, 10, 8. And we can go further - some numbers like 77 will only have their hands on the left-ish side of the face, at 7 and 11.

To make it even easier, let's rotate the clock anti-clockwise by one hour, so the number 1 is straight up and the number 7 is straight down.

Let us give these patterns names.

Numbers like 1, and 13, with only one clock hand: Full

Numbers with clock hands only on the left, like 77: First South Quarter

Numbers with clock hands only on the right, like 6: Last South Quarter

Numbers with clock hands on all sides, like 20 (10,5,2,1,8): New

Write a program that given some number n, returns it's phase, and how many other numbers have that same phase, but are smaller than n.

For example 13 has the phase Full, and there is 1 other number below it, so the result should be "Full 1"

2, 3, 4, 5, and 6 are all phase Last South Quarter, so they would be "LSQ 0" "LSQ 1", "LSQ 2", "LSQ 3", "LSQ 4"

7 has phase First South Quarter, and in fact is the first such number, so it will be "FSQ 0".

8 has factors 4, 2, and 1, which are on both the left and right side, so it's phase is New. It's the first full number, so "New 0"

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\$\endgroup\$
  • 1
    \$\begingroup\$ Hm, as it is right now, it looks like the "how many other numbers have that same phase, but are smaller than n" is an overcomplication. Also, is the 1 hand to the left, right or neither? Similarly for the 7 hand. I also suggest allowing any 4 unique identifiers for the phases. \$\endgroup\$ – Erik the Outgolfer Jun 30 '19 at 16:50
1
\$\begingroup\$

Switch the colour of the largest non-unique connected shape

Given a rectangular grid of square cells, find the non-unique connected shapes with the largest area, and switch their colour

Input

  • A rectangular grid of cells, each of which has 1 of 2 distinct values ("colours")
  • You can choose to accept any of
    • an image with only 2 distinct pixel colours
    • text with only 2 distinct characters (also allowing newlines for forming a rectangle)
    • a 2d array, with each element having 1 of 2 distinct values
    • a 1d array, plus a width and/or height

The 2 distinct values will be referred to as "colours", but the rules apply similarly for all of the permitted formats

Output

  • A rectangular grid of cells in the same format as the input, using the same 2 colours
  • For each shape required to be changed, all of its cells have been switched to the other colour

Rules

  • Each cell is part of a connected shape, which contains all cells of the same colour that can be reached by a path made up only of vertical or horizontal steps to adjacent cells of the same colour (no diagonal steps)
  • The grid does not wrap: a shape cannot be connected across the outer boundary
  • A shape is identical to another if it can be made to coincide exactly with it by any combination of
    • translation
    • rotation by an integer multiple of 90 degrees
    • reflection in any vertical or horizontal line
    • switching its colour
  • A shape is unique if no other shape is identical to it
  • The area of a shape is the number of cells it contains
  • The shapes to be changed are those with the largest area, of those that are non-unique
  • If 2 or more distinct shapes are non-unique and have the largest area, all instances of each distinct shape must be changed
  • If there are no non-unique shapes, the output is the same as the input
  • A grid (input or output) may sometimes contain only 1 of the 2 colours

Test cases

Each test case is an input followed by its unique correct output

.  .

..  ..

.#  #.

.#  .#
..  ..

.#  #.
#.  .#

..#  ...
...  ...
.#.  ...

.......  .......
##.....  .......
#.....#  .......
.....##  .......

....##.  ....##.
##..##.  ....##.
#.....#  .......
.....##  .......

#.....###.  ..........
#.......#.  ..........
##...##...  ..........
.....##...  ..........
##........  ..........
##..####..  ....####..

.......###  .......###
..##..####  ......####
..#..###.#  .....#####
....###..#  ....######
...#######  ...#######

.......###  #######...
.##...####  ######....
.#...###.#  #####.....
....###..#  ####......
...#######  ###.......

........####  ########....
.###...#...#  ########....
.#..#.#.##.#  ##..##..##..
.###.###...#  ####........
....########  ####........

........####  ########....
.###...#...#  ########....
.#..#.#....#  ##..##......
.###.###...#  ####........
....########  ####........

The same test cases with colour coding for human reading (click image for larger version):

test cases with colour coding

Scoring

This is . Your score is the number of bytes in your source code. For each language, the code with the lowest score wins


Sandbox thoughts

  • Any important/useful test cases welcome
  • Is there a more useful format for 2d test cases?
  • Are there 2 distinct characters that would make human reading easier?
  • Is this a duplicate?
  • Can anything be made clearer or more succinct?
  • I'm also trying to think of a better name
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  • 1
    \$\begingroup\$ I think using "remove" and "change" to mean the same thing is confusing. If I understand correctly, "removing" means to change the colour of, right? That wasn't very intuitive to me on my first reading. \$\endgroup\$ – FryAmTheEggman Jun 29 '19 at 16:52
  • \$\begingroup\$ Ah good point. Thank you. I will try and make that consistent throughout \$\endgroup\$ – trichoplax Jun 29 '19 at 19:16
1
\$\begingroup\$

Some enchanted avening

(you may see a stranger across a crowded room).

This is one part of a multi-part series inspired by various built-ins in R. Credit goes to digEmAll for suggesting this one.

ave calculates particular grouped values of a list.

For example, we would group x in the following way based on the criteria given in f:

x = [2, 1, 3, 5, 4, 1, 5, 5]
f = [[1, 2, 2, 2, 1, 2, 1, 1], [1, 1, 2, 2, 2, 1, 1, 2]]

     x f1 f2
[1,] 2  1  1    -> group [1,1]
[2,] 1  2  1    -> group [2,1]
[3,] 3  2  2    -> group [2,2]
[4,] 5  2  2    -> group [2,2]
[5,] 4  1  2    -> group [1,2]
[6,] 1  2  1    -> group [2,1]
[7,] 5  1  1    -> group [1,1]
[8,] 5  1  2    -> group [1,2]

Then for each group, we apply a given function (in R, the default is mean), let's say sum:

group [1,1]: 2, 5 -> sum = 7
group [2,1]: 1, 1 -> sum = 2
group [2,2]: 3, 5 -> sum = 8
group [1,2]: 4, 5 -> sum = 9

Then we replace each value in the group by the group sum, resulting in an output of:

[7, 2, 8, 8, 9, 2, 7, 9]

Inputs:

  • a list x of integers
  • a list of lists f or an arbitrary number of lists, each of length equal to x; these are the factors to group on
  • a black-box function FUN that takes a list of integers and returns a single integer value

Output

  • a list o of length equal to x where each element o[i] is equal to FUN(group(x[i])), or as the documentation says:

    A numeric vector, say y of length length(x). If f is g1, g2, e.g., y[i] is equal to FUN(x[j], for all j with g1[j] == g1[i] and g2[j] == g2[i]).

Rules

  • Input can be in any order and in many flexible output formats.
  • You may assume that the outputs will always result in integers.
  • If your language has a builtin for this for some reason, please also implement your own solution.

Sandbox questions/notes:

  • I've done two of these so far and found a reference to a musical that is somewhat appropriate, any suggestion is appreciated there.
  • Need to add test cases
  • Need to work a bit harder on the explanation of how ave works.
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  • 1
    \$\begingroup\$ You could call this something along the lines of "Ave Maria von Trapp"? Aside from that I understood your description well enough to write a (poor) answer. \$\endgroup\$ – FryAmTheEggman Jun 26 '19 at 19:45
1
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Manage a todo list using Cypher (WIP)

Introduction

A list is a common, well-understood data structure. Neo4j's property graph model can represent any data structure. Using the Cypher query language, write a collection of statements for managing a todolist

Challenge

Manage a todo list using parameterized Cypher.

Todo list items are composed of two pieces of information:

  • todo:string - the textual content describing the thing to do
  • completed:boolean - whether this todo has been done

Todo list operations:

  • add new, view, edit, remove, complete, un-complete individual todo list item
  • re-order todo list item
  • view all items
  • view all completed items
  • view all "active" items (items not yet completed)
  • complete all todo list items

Considerations:

  • empty todo list

Out of scope:

  • multiple lists

Answer Format

For each operation, provide a code block of Cypher. Identify the operation with its description. Separate each operation with a --- line. Like this...

  1. Create an empty node:
CREATE ()

  1. Create a generic relationship:
CREATE ()-[:RELATES_TO]->()

Proposed tags

[cypher] [graph-theory]

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\$\endgroup\$
  • \$\begingroup\$ (1) This is a long way from being self-contained. What's Neo4j? (Sounds like a Java library). What's Cypher? (2) The operations need more explanation, particularly those which rely on properties which haven't been mentioned. (Reorder? But there's no position-in-order property. Operations on individual item: what's its identity?). (3) This site discourages questions which restrict answers to a single language unless there's a good reason for the restriction. I don't see a good reason here. \$\endgroup\$ – Peter Taylor Jul 6 '19 at 7:54
1
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Can the cursor reach the bottom?

A cursor position is valid if either of its two sides touches whitespace (i.e. a space or a newline(CR+LF or LF, depending on your OS)). The input will always consist of valid cursor positions.

This takes one input(a character matrix), and for a cursor on the up right corner of the input, can the cursor reach the bottom of the input?

Example input:

 ..... Same, delete text like this in order
 ......
. . . .
.      Same to get normal input
...... Same

The cursor can reach the bottom in this case. This process of moving the cursor will work: down, right(touches spaces on the left), down(touches spaces on the right), down, right(touches spaces on both sides) 6 times, and down(touching spaces and a linefeed).

Notably, this will also work:

  Code Golf deletes trailing whitespace by default
..
. trailing

The cursor starts at the up-right corner. After moving right two times, it can move down (due to touching a newline character). Then, it can move down, which touches the bottom of the line.

This example will not work:

 ...
... Same reason as above

The cursor cannot move down, as there is no sufficient whitespace to be touched.

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1
\$\begingroup\$

Posted here

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\$\endgroup\$
  • 1
    \$\begingroup\$ Interesting challenge, but I'm afraid a lot of trivial solutions exist. E.g. 123 which prints 123 in many languages. More interesting would be to require all three/four characters to be unique, and that they be printed in reverse. \$\endgroup\$ – Adám Jul 8 '19 at 20:04
  • 2
    \$\begingroup\$ now that this has been posted, you can edit it to only include a link to your post and delete it :-) \$\endgroup\$ – Giuseppe Jul 9 '19 at 18:50
1
\$\begingroup\$

There's an echo in my array... echo in my array... my array...

Posted. Thanks for all of the suggestions and happy golfing!

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\$\endgroup\$
  • \$\begingroup\$ "0≤n<1000" The input has 0–1000 elements or the elements are in the range 0–1000, or both? \$\endgroup\$ – Adám Jul 8 '19 at 21:24
  • \$\begingroup\$ Can there not be multiple correct solutions? \$\endgroup\$ – Adám Jul 8 '19 at 21:26
  • \$\begingroup\$ Will the echo ever begin at the first element? \$\endgroup\$ – Adám Jul 8 '19 at 21:26
  • \$\begingroup\$ I'm not sure I fully understand how the echo works. Why can [2,4,6] not be [1,2,3] with an echo overlapping at the first element? \$\endgroup\$ – Adám Jul 8 '19 at 21:31
  • \$\begingroup\$ In fact, would there be one solution for each step, so dividing the input by 2 is always a valid solution? \$\endgroup\$ – Adám Jul 8 '19 at 21:32
  • \$\begingroup\$ @Adám ah yes, that's why echo cannot begin at the first element. The echo'd version will always be longer than the original un-echoed version. I'll clarify that. \$\endgroup\$ – 640KB Jul 8 '19 at 21:33
  • \$\begingroup\$ @Adám have updated rules and test cases from your comments. Thanks! \$\endgroup\$ – 640KB Jul 9 '19 at 18:32
  • \$\begingroup\$ As suggestion: if there is no echo, don't output nothing or false - the challenge is to correct the echo. If there is none, the echo is corrected to be... no different from the input. In a bid for consistency, I would therefore suggest that if there is no echo, they should output the original input, since that is the 'normal' version of the array. \$\endgroup\$ – Geza Kerecsenyi Jul 10 '19 at 8:09
  • \$\begingroup\$ Also, I'd suggest to make the program return the shortest possible array in the case of multiple solutions, to remove the most possible reverb - i.e choose the one that removes the most values from the input. \$\endgroup\$ – Geza Kerecsenyi Jul 10 '19 at 13:42
  • \$\begingroup\$ @GezaKerecsenyi I've been trying to come up with a case where there are multiple solutions, and cannot. You can easily have many echo'd versions for a given un-echo'd version, but there seems to only be one or zero un-echo'd versions for an echo'd version. I'm not a mathematician, so I cannot conclusively prove this, and I'm happy to be proven wrong, but I don't see a way that a correctly-constructed echo'd version could produce more than one answer. \$\endgroup\$ – 640KB Jul 10 '19 at 14:52
  • 1
    \$\begingroup\$ @gwaugh after further consideration, I have come to the conclusion that you're correct. It's like a Fourier transform: every wave function always have a unique value, either in terms of phase or magnitude. Here, the phase is always different, and since the phase is shifted, the 'transform' of these numbers (imagining they are Y values at the X point of their index) must also be unique. So feel free to remove that rule - there can never be two answers. \$\endgroup\$ – Geza Kerecsenyi Jul 10 '19 at 17:12
1
\$\begingroup\$

Story

I began studying the Collatz Conjecture

And noticed this pattern in the numbers that go to 1 in one odd step, like 5,10,20,21,40,42... and looke in up on OEIS and found this formula.

\$floor(sqrt(4*n + 1)) - 1\$

Which can plot these numbers in their natural order like so;

\$\frac{\left(8\cdot2^{\operatorname{floor}\left(\sqrt{4\operatorname{floor}\left(x\right)+1}\right)}-2^{\left(\operatorname{floor}\left(\sqrt{4\operatorname{floor}\left(x\right)+1}\right)-1-\operatorname{floor}\left(\frac{\left(4\operatorname{floor}\left(x\right)+1-\operatorname{floor}\left(\sqrt{4\operatorname{floor}\left(x\right)+1}\right)^2\right)}{2}\right)\right)}\right)}{3}\$

Then I looked at numbers going to 1 in two steps, like 3,6,12,13,24,26...
Where I found another pattern that I could not find a formula for on OEIS

long nth(int n){if(n>241)return -1;return (((1<<Y[n]+5)-(1<<1+Y[n]-((Z[n]&1)+Z[n]*3)))/3-(1<<Y[n]-2*X[n]-(2*(Z[n]&1)+Z[n]*3)))/3;}

With X[],Y[] and Z[] being these lookup-tables

 int[]X=new int[]{
 0, 
 0, 
 0,  1, 
 0,  1, 
 0,  1,  2, 
 0,  1,  2,                              0,
 0,  1,  2,  3,                          0,                          0, 
 0,  1,  2,  3,                          0,  1,                      0, 
 0,  1,  2,  3,  4,                      0,  1,                      0,  1, 
 0,  1,  2,  3,  4,                      0,  1,  2,                  0,  1, 
 0,  1,  2,  3,  4,  5,                  0,  1,  2,                  0,  1,  2,
 0,  1,  2,  3,  4,  5,                  0,  1,  2,  3,              0,  1,  2,                  0,
 0,  1,  2,  3,  4,  5,  6,              0,  1,  2,  3,              0,  1,  2,  3,              0,              0, 
 0,  1,  2,  3,  4,  5,  6,              0,  1,  2,  3,  4,          0,  1,  2,  3,              0,  1,          0, 
 0,  1,  2,  3,  4,  5,  6,  7,          0,  1,  2,  3,  4,          0,  1,  2,  3,  4,          0,  1,          0,  1, 
 0,  1,  2,  3,  4,  5,  6,  7,          0,  1,  2,  3,  4,  5,      0,  1,  2,  3,  4,          0,  1,  2,      0,  1, 
 0,  1,  2,  3,  4,  5,  6,  7,  8,      0,  1,  2,  3,  4,  5,      0,  1,  2,  3,  4,  5,      0,  1,  2,      0,  1,  2, 
 0,  1,  2,  3,  4,  5,  6,  7,  8,      0,  1,  2,  3,  4,  5,  6,  0,  1,  2,  3,  4,  5,      0,  1,  2,  3,  0,  1,  2,      0, 
 0,  1,  2,  3,  4,  5,  6,  7,  8,  9,  0,  1,  2,  3,  4,  5,  6,  0,  1,  2,  3,  4,  5,  6,  0,  1,  2,  3,  0,  1,  2,  3,  1, 2
 };
 int[]Y=new int[]{
 0, 
 1, 
 2,  2, 
 3,  3, 
 4,  4,  4, 
 5,  5,  5,                              5,
 6,  6,  6,  6,                          6,                          6, 
 7,  7,  7,  7,                          7,  7,                      7, 
 8,  8,  8,  8,  8,                      8,  8,                      8,  8, 
 9,  9,  9,  9,  9,                      9,  9,  9,                  9,  9, 
10, 10, 10, 10, 10, 10,                 10, 10, 10,                 10, 10, 10,
11, 11, 11, 11, 11, 11,                 11, 11, 11, 11,             11, 11, 11,                 11,
12, 12, 12, 12, 12, 12, 12,             12, 12, 12, 12,             12, 12, 12, 12,             12,             12, 
13, 13, 13, 13, 13, 13, 13,             13, 13, 13, 13, 13,         13, 13, 13, 13,             13, 13,         13, 
14, 14, 14, 14, 14, 14, 14, 14,         14, 14, 14, 14, 14,         14, 14, 14, 14, 14,         14, 14,         14, 14, 
15, 15, 15, 15, 15, 15, 15, 15,         15, 15, 15, 15, 15, 15,     15, 15, 15, 15, 15,         15, 15, 15,     15, 15, 
16, 16, 16, 16, 16, 16, 16, 16, 16,     16, 16, 16, 16, 16, 16,     16, 16, 16, 16, 16, 16,     16, 16, 16,     16, 16, 16, 
17, 17, 17, 17, 17, 17, 17, 17, 17,     17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17, 17,     17, 17, 17, 17, 17, 17, 17,     17, 
18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18
};
int[]Z=new int[]{
0, 
0, 
0,  0, 
0,  0, 
0,  0,  0, 
0,  0,  0,                              1,
0,  0,  0,  0,                          1,                          2, 
0,  0,  0,  0,                          1,  1,                      2, 
0,  0,  0,  0,  0,                      1,  1,                      2,  2, 
0,  0,  0,  0,  0,                      1,  1,  1,                  2,  2, 
0,  0,  0,  0,  0,  0,                  1,  1,  1,                  2,  2,  2,
0,  0,  0,  0,  0,  0,                  1,  1,  1,  1,              2,  2,  2,                  3,
0,  0,  0,  0,  0,  0,  0,              1,  1,  1,  1,              2,  2,  2,  2,              3,              4, 
0,  0,  0,  0,  0,  0,  0,              1,  1,  1,  1,  1,          2,  2,  2,  2,              3,  3,          4, 
0,  0,  0,  0,  0,  0,  0,  0,          1,  1,  1,  1,  1,          2,  2,  2,  2,  2,          3,  3,          4,  4, 
0,  0,  0,  0,  0,  0,  0,  0,          1,  1,  1,  1,  1,  1,      2,  2,  2,  2,  2,          3,  3,  3,      4,  4, 
0,  0,  0,  0,  0,  0,  0,  0,  0,      1,  1,  1,  1,  1,  1,      2,  2,  2,  2,  2,  2,      3,  3,  3,      4,  4,  4, 
0,  0,  0,  0,  0,  0,  0,  0,  0,      1,  1,  1,  1,  1,  1,  1,  2,  2,  2,  2,  2,  2,      3,  3,  3,  3,  4,  4,  4,      5, 
0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  1,  1,  1,  1,  1,  1,  1,  2,  2,  2,  2,  2,  2,  2,  3,  3,  3,  3,  4,  4,  4,  4,  5, 5
};

Challenge

The challenge is to write a "reasonably fast" function or expression that replaces and extends these lookup tables.
Think of the lookup tables as a 3D structure. Pictured is the top 720 boxes of this structure.

challenge

Input

An integer which is the index of a cube in the structure. You can assume the input will be in the range 0 to 719 inclusive.

Output

The x,y,z coordinates for the given index. Assuming the input is between 0 and 719 the output ranges are x, 0 to 13 y, 0 to 27 z, 0 to 8

It's fine to accept and return larger indexes correctly just not required.

Examples

    i  ->   x   y   z
    0  ->   0,  0,  0
   12  ->   0,  5,  1
   30  ->   4,  8,  0
   65  ->   2, 11,  1
  100  ->   0, 13,  2
  270  ->   1, 19,  3
  321  ->   1, 20,  6
  719  ->   1, 27,  8

If you collapse the z-coordinate, then the structure is indexed top-down left right like shown below; Examples are marked in square brackets []

Y,Z 0,
 0   | [0]  
 1   |  1 
 2   |  2   3 
 3   |  4   5 
 4   |  6   7   8                                1,
 5   |  9  10  11                                 |[12]                           2,
 6   | 13  14  15  16                             | 17                             | 18 
 7   | 19  20  21  22                             | 23  24                         | 25 
 8   | 26  27  28  29 [30]                        | 31  32                         | 33  34 
 9   | 35  36  37  38  39                         | 40  41  42                     | 43  44 
10   | 45  46  47  48  49  50                     | 51  52  53                     | 54  55  56                    3,
11   | 57  58  59  60  61  62                     | 63  64 [65] 66                 | 67  68  69                     | 70                4,
12   | 71  72  73  74  75  76  77                 | 78  79  80  81                 | 82  83  84  85                 | 86                 | 87 
13   | 88  89  90  91  92  93  94                 | 95  96  97  98  99             [100] 101 102 103                |104 105             |106 
14   |107 108 109 110 111 112 113 114             |115 116 117 118 119             |120 121 122 123 124             |125 126             |127 128 
15   |129 130 131 132 133 134 135 136             |137 138 139 140 141 142         |143 144 145 146 147             |148 149 150         |151 152 
16   |153 154 155 156 157 158 159 160 161         |162 163 164 165 166 167         |168 169 170 171 172 173         |174 175 176         |177 178 179        5,
17   |180 181 182 183 184 185 186 187 188         |189 190 191 192 193 194 195     |196 197 198 199 200 201         |202 203 204 205     |206 207 208         |209    6, 
18   |210 211 212 213 214 215 216 217 218 219     |220 221 222 223 224 225 226     |227 228 229 230 231 232 233     |234 235 236 237     |238 239 240 241     |242     |243 
19   |244 245 246 247 248 249 250 251 252 253     |254 255 256 257 258 259 260 261 |262 263 264 265 266 267 268     |269[270]271 272 273 |274 275 276 277     |278 279 |280
20   |281 282 283 284 285 286 287 288 289 290 291 |292 293 294 295 296 297 298 299 |300 301 302 303 304 305 306 307 |308 309 310 311 312 |313 314 315 316 317 |318 319 |320[321]
  X->|  0   1   2   3   4   5   6   7   8   9  10 |  0   1   2   3   4   5   6   7 |  0   1   2   3   4   5   6   7 |  0   1   2   3   4 |  0   1   2   3   4 |  0   1 |  0   1  

Note that at even y-coordinates the structure expands in the x-direction, and at 0 and 5 mod 6 in the z-direction. Expect for the very top block.

Rules

This is code-golf, the shortest code in bytes wins.

Reasonably fast As an additional requirement although not a competition of fastest code,
the code must still be shown to compute coordinates in a reasonable amount of time. You may for example use try it online and run a loop through all coordinates under 720 without exceeding the time limit of a minute, printing is optional.

If you fail this rule, mark your answer with non competing

"storing information as you go" is forbidden. For example executing f(100) should not depend on having computed f(99) previously.

Lookup tables are allowed but included in bytecount so aim to make them sparse if you choose to use them.

Example code

non-competing

coord coords(int index){
int a=0,b=0,c=0;
int x=0,y=0,z=0;
long n,k,one;  
n = k = 3;
int t=0;
while(t<index){
int s=0;k++;n=k;
while(n>1 && s<4){ n/=n&-n;n=n*3+1; n/=n&-n;s++;}
if(s==2)t++;
}
n=k; 
one=n&-n;k = one;while(k>1){k>>=1;c++;} n=3*n+one;
one=n&-n;k = one;while(k>1){k>>=1;b++;} n=3*n+one;
one=n&-n;k = one;while(k>1){k>>=1;a++;} 
coord r;
r.x = (b-c-1)>>1;
r.y = a-5;
r.z = (a-b-2)/6 +(a-b-4)/6;
return r;
}

Try it online!

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  • \$\begingroup\$ Will the input always be between 0 and 321 (inclusive)? \$\endgroup\$ – streetster Jul 10 '19 at 6:27
  • \$\begingroup\$ Good question, let's go with 797 @streetster \$\endgroup\$ – PrincePolka Jul 10 '19 at 10:59
  • \$\begingroup\$ @streetster 719.. i counted the boxes wrong, good thing I began in the sandbox \$\endgroup\$ – PrincePolka Jul 11 '19 at 17:58
1
\$\begingroup\$

Decode a RISC-V J-type immediate

RISC-V is an open processor instruction set, which defines a somewhat typical RISC instruction set. However, in order to make decoding simpler in hardware, the encoding for immediate values tends to be quite complex, with the bits essentially shuffled around. And the worst offender for that is without a doubt the type J (jump) instruction type.

So, the challenge is, given a (non-compressed) RISC-V instruction word, decode and output its type J immediate part.

A type J instruction has the following format:

   31      30-21     20       19-12   11-7  6-0
|imm[20]|imm[10:1]|imm[11]|imm[19:12]| rd |opcode|

The only fields we are interested in are the imm fields. The immediate is sign extended, and its least significant bit is always 0, so the immediate (in term of instruction bits) is:

    31-20       19-12       11        10-1     0
|...inst[31]|inst[19:12]|inst[20]|inst[30:21]| 0 |

Sample pseudocode: 0xFFF00000 * ((instr >> 31) & 1) | (instr & 0x000FF000) | ((instr & 0x100000) >> 9) | ((instr & 0x7FE00000) >> 20).

Test cases

I: 0x4DFAB06F (j 0xABCDE)
O: 0x000ABCDE

I: 0xFD9FF0EF (jal ra, -0x28)
O: 0xFFFFFFD8

I: 0x8000006F (j -0x100000)
O: 0xFFF00000

The answer with the smallest byte count wins, standard loopholes apply, etc... Your program may take input and write output in any format it requires.

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  • 1
    \$\begingroup\$ It took a bit of puzzling to figure out the second code block. The ... notation is liable to misunderstanding (I'm not sure whether JS developers would find it more or less confusing), and there's no clear reason for 10-5 and 4-1 to be split up. This is one case where a reference implementation in generic C-like pseudocode could help: I think 0xfff00000 * ((imm >> 31 & 1)) | (imm & 0x000ff000) | ((imm & 0x00100000) >> 9) | ((imm & 0x7fe00000) >> 20) is correct and fairly generic. (In particular, I've deliberately avoided making assumptions about how the sign bit is treated under >>). \$\endgroup\$ – Peter Taylor Jul 16 '19 at 8:10
  • 1
    \$\begingroup\$ @PeterTaylor I copied the instruction format diagram from the RISC-V specification and I didn't realize the 10-5 and 4-1 parts could be merged. Oops. And I added a pseudocode for the decoding. \$\endgroup\$ – TuxCrafting Jul 16 '19 at 11:38
1
\$\begingroup\$

Alphanumeric Line and Curve Counting

Posted here.

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1
\$\begingroup\$

Bits and Bytes constant generation

In this challenge, you have to generate the shortest Bits and Bytes program that outputs an integer input. For the simplicity of the challenge, you only have to search with ! and <.

Bits and Bytes quick reference

Bits and Bytes operates on a one-byte accumulator. There are 4 operations (only 2 are neccecary for this challenge):

  • ! : Invert all of the bits in the accumulator
  • < : Shifts all bits in the accumulator one bit to the right. The leftmost bit becomes a 0 and the rightmost bit is discarded.
  • > : Shift right
  • @ : Swap nybbles

Input / Output

Input will be two integers. The first integer sets the accumulator to the value of that integer. The second integer indicates the resulting value. Your program should output the shortest program in Bits and Bytes that sets the accumulator to that value.

Examples

0
255
!
0
4
!<!<!<

This is a contest; the shortest program wins.

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  • 1
    \$\begingroup\$ I'd recommend having the question be self contained and explaining what the instructions actually do \$\endgroup\$ – Jo King Jul 21 '19 at 11:34
  • 2
    \$\begingroup\$ This is similar enough to some previous challenges that I wouldn't be surprised if someone finds a dupe. Also, should there be a second input for the starting value of the accumulator? \$\endgroup\$ – Peter Taylor Jul 21 '19 at 23:04
1
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WANTEDM?VEMENTANDACALMCOURSE?FE???UENCE

Challenge

Inspired by puzzles appearing on my website's chat, your job (should you choose to accept it) is to accept a string (say (?@Nbgkx¨¾ÃÐÕã÷øĆĊċĎďěĨīĺŏšŴŹǣǩǮ˘͵ΖΫΰξρφ) and:

  • Find the Unicode points for the string: [40, 63, 64, 78, 98, 103, 107, 120, 168, 190, 195, 208, 213, 227, 247, 248, 262, 266, 267, 270, 271, 283, 296, 299, 314, 335, 353, 372, 377, 483, 489, 494, 728, 885, 918, 939, 944, 958, 961, 966]
  • Find the differences between elements: [23, 1, 14, 20, 5, 4, 13, 48, 22, 5, 13, 5, 14, 20, 1, 14, 4, 1, 3, 1, 12, 13, 3, 15, 21, 18, 19, 5, 106, 6, 5, 234, 157, 33, 21, 5, 14, 3, 5]
  • For every element in the differences between elements:
    • If the element is less than 27, add it by 64 and output it converted to a Unicode character (e.g. 1 -> "A", 2 -> "B", \$\ldots\$ ).
    • If the element is greater than or equal to 27, output a non-alphabet character ([^A-Za-z])

Test Cases

The test cases output in uppercase and use the question mark for the non-alphabet character.

(?@Nbgkx¨¾ÃÐÕã÷øĆĊċĎďěĨīĺŏšŴŹǣǩǮ˘͵ΖΫΰξρφ --> WANTEDM?VEMENTANDACALMCOURSE?FE???UENCE
!1CRYkly¤´ÉãýĉĎġĢİĴķņŊŏŖťűŷ --> PROGRAM?PUZZLESANDCODEGOLF
!$37<CR^deswz¤«®¶·ÃÏÔâéîā --> CODEGOLFANDC?GCHALLENGES
!5=BShqt¢¹ÇÍÜôþēĠİĵĹňŞţŵƉƑƖƢƣƽǖǚǩǰȃ -> THEQUIC?WNFOXJUMPEDOVERTHELAZYDOGS

Notes

  • The difference between the Unicode points for the string will always be greater than 0.
  • The input's Unicode points will be strictly increasing.
  • You may output in lowercase.
  • The non-alphabet character does not need to be consistent.
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  • \$\begingroup\$ I suggest using less than or equal to 26, so that Z can be represented \$\endgroup\$ – wastl Aug 1 '19 at 12:59
  • \$\begingroup\$ @wastl Yeah, done \$\endgroup\$ – MilkyWay90 Aug 1 '19 at 16:07
  • 1
    \$\begingroup\$ What stops us from just adding 97 to all the differences, since outside that range is non-alphabetical? \$\endgroup\$ – Jo King Aug 2 '19 at 4:09
  • 1
    \$\begingroup\$ @JoKing Nothing stops you from doing that. \$\endgroup\$ – MilkyWay90 Aug 2 '19 at 4:54
1
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I've had an idea for a coding challenge, but I'm a). not 100% certain it's not already been done, and b) not sure if some of the golfing specific languages will trivialise it too much.

Basically the premise is thus:

The scoring for your question is achieved in the following fashion:

  1. All comments are removed from your script
  2. +1 point per character in your script
  3. +1 point per character in your output
  4. The following algorithm applied to the concatonation of your script and your output:
    • +1 point the first time a character shows up
    • -1 point the second time a character shows up
    • -2 points the third time
    • -4 points the fourth time
    • -8 points the fifth
    • double ad infinitum
  5. The scores for character repetition above are cumulative. So, a would yield 2 points (1 for length, 1 for first occurance of character). aa would yield 2 points (2 for length, +1 for first instance, -1 for second instance). aaa would yield 1 point (3 for length, +1 for 1st, -1 for 2nd, -2 for third)

Rules:

  • No standard loopholes

I'm also not even sure what I would tag this question as.

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  • 2
    \$\begingroup\$ As far as tagging goes: code-challenge. \$\endgroup\$ – Wheat Wizard Aug 2 '19 at 14:12
  • 1
    \$\begingroup\$ One issue is I could just write a comment with 65,000 unicode characters in it. \$\endgroup\$ – Redwolf Programs Aug 2 '19 at 14:45
  • \$\begingroup\$ @RedwolfPrograms ah so there needs to be a rule excluding comments \$\endgroup\$ – Scoots Aug 2 '19 at 14:49
  • \$\begingroup\$ Hmm and I also need a creative way to say “script cannot simply be print ‘abcdefg...’ \$\endgroup\$ – Scoots Aug 2 '19 at 14:51
  • 2
    \$\begingroup\$ @Scoots Well, that's where it gets complicated. This could also be considered a code-bowling challenge in a way, since the goal is to make the longest source code (or output) possible. The issue with code bowling questions is that they often have exploitable loopholes like comments, regexes, variable names, etc. I'd find a way to work this into the scoring, such as reducing points for source code lengths and adding points for output length \$\endgroup\$ – Redwolf Programs Aug 2 '19 at 14:52
  • \$\begingroup\$ @RedwolfPrograms that falls afoul of a for loop and a given language’s chr function. This will take some thinking. \$\endgroup\$ – Scoots Aug 2 '19 at 14:57
  • \$\begingroup\$ @Scoots Maybe base it on some other element, like execution time? \$\endgroup\$ – Redwolf Programs Aug 2 '19 at 14:59
  • 1
    \$\begingroup\$ @RedwolfPrograms Nah that's too contingent on circumstances outside our control (how busy is the server when it runs the script etc)... I'm going to think on this for a while. Maybe something creative with exclusives between script and output \$\endgroup\$ – Scoots Aug 2 '19 at 15:45
  • 1
    \$\begingroup\$ @Scoots I haven't seen too many good posts based on getting the longest source code/output, and I'll be excited to see something new. Good luck! \$\endgroup\$ – Redwolf Programs Aug 2 '19 at 16:00
  • 1
    \$\begingroup\$ I only see a scoring system, but no challenge. Also, in languages like Unary or Whitespace it would be trivial to get arbitrarily large negative scores - and in most languages you can add effective no-ops. I think this kind of thing has been tried before, but it may not have made it past the sandbox because it has big problems which can't really be fixed. \$\endgroup\$ – Peter Taylor Aug 5 '19 at 7:53
  • 1
    \$\begingroup\$ @PeterTaylor The challenge would be to get the highest possible positive score of course, but sadly my thinking has led me to concur with the rest of your statement. Sandbox being the filter it is supposed to be :) \$\endgroup\$ – Scoots Aug 5 '19 at 16:58
1
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This puzzle is based on this Math.SE post.

Assume I have some number of black shirts and some number of white shirts, both at least 1. Both colors of shirt have a non-zero durability. All shirts of a given color start with the same durability.

Every day, I pick out a clean shirt to wear, and it becomes dirty. Once I run out of all clean black shirts or all clean white shirts, I wash all my dirty shirts of both colors and start over. Clean shirts do not get washed. Whenever a shirt gets washed, its durability goes down by one. Immediately after washing, if the durability of a shirt reaches 0, it must be thrown out.

When picking which shirt to wear of a particular color, I always choose a shirt with the highest durability of that color to ensure even wear and tear among shirts.

Challenge:

Take in a sequence of two characters of arbitrary length (eg. b b b w b w w b...) representing my choice of shirt to wear on that day. Continue execution until either my last black shirt or my last white shirt is thrown out. Once this occurs, stop consuming input and halt execution immediately. Note that the program must not consume any more input than is required before halting.

Inputs:

Number of black shirts, number of white shirts, durability of black shirts, durability of white shirts, and an arbitrary number of two single characters, your choice (eg. b and w)

Output

None. The program must simply halt when the last shirt of either color is thrown away.

Test cases

1 1 1 1 b

1 999 1 999 b

1 999 1 999 w w w w w w w w b

2 999 1 999 b w w w b

2 999 2 999 b w w w b w b w w w b

5 3 6 1 w w w w w b b b b b b b b b b b b b b w

General rules:

  • This is , so shortest answer in bytes wins.
  • Default input rules apply for the first four arguments. For the arbitrarily long input sequence after the first four arguments, input must come from a source which can provide input one character or byte at a time, of theoretically infinite length, such as STDIN or some other stream.
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  • 1
    \$\begingroup\$ How exactly are you going to test that only a certain amount of input has been used? \$\endgroup\$ – Jo King Aug 8 '19 at 5:04
  • 2
    \$\begingroup\$ Typically you should address concerns made in Sandbox before posting to main. \$\endgroup\$ – Jo King Aug 8 '19 at 5:31
1
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Calculate mobile data coverage

Background

You've been hired by the HQ of Vodafizon - a relatively new mobile network provider interested in spreading to the global market. In particular, your job description involves working as a marketing rep to produce ads for each country, where you give a figure of the data coverage, as a percentage, in that country. You get this data from the data scientists, but you've started to notice a pattern: the number always seems to be 98%, 99% or 100% (which, in your experience, seems to be far too high). Despite your trust in Vodafizon, you seem to find this suspicious, so you write your own program to investigate, ensuring maximum precision, even implementing your own floating-point and circle rasterization algorithm to minimize error. You end up making a 112KB monster of a program, but the result confirms your suspicions: these figures are, for the most part, made up by the data scientists, to try and exaggerate their claims.

When you mention this discovery to a coworker, they act surprised at first, but later tell you to keep quiet: upper management probably know about the forgery, and in fact endorse it. Telling them that you know their dirty secret could will result in losing your job.

But here's the thing: you know that advertising these fake numbers could result in massive lawsuits to Vodafizon, the effects of which could result in you getting laid off. You know you can't risk getting fired, but just using the data scientists' figures could be disastrous in the long term.

After consulting Workplace SE, you come up with a plan: keep using your program, but hide it from your superiors. The only issue is, that the data scientists responsible for providing you the data also happen to be the makeshift sysadmins in Vodafizon HQ, so your program can't attract too much attention to itself. 112KB is far more than Vodafizon uses on average (they prefer to split code into lots of tiny files), so when filtering through by file type, the sysadmins will easily see this file as potentially twenty times larger than all the others. So clearly, you need to compress it, without sacrificing the accuracy.

Input

The input will consist of a nested array of form [[x, y], [x, y]] (or alternatively an object of form [{"x":x, "y":y}, {"x":x, "y":y}]) of line segments, in clockwise order, defining the border of a country.

The input will also contain a nested array of form [[x, y, strength], [x, y, strength]] (or an object of form [{"x":x, "y":y, "s":strength}, {"x":x, "y":y, "s":strength}]), which will describe the location of the mobile data towers, and the strength: the radius (or diameter, you can request either in your answer (but not both)) of the circle in which that given tower provides mobile data.

Output

Your program should output an approximation of the mobile data coverage of the input given. Of course, this is impossible to get perfect (unless you live in Indiana, that is), so you need to provide an approximation, but while reducing your byte count as much as possible. Note that your program must halt by itself before 5 seconds of runtime (for any test where the number of towers is less than or equal to 500, and the number of edges is less than 100), or alternatively continuously provide output such that once it is stopped after 5 seconds, the last output will be taken as the result.

Scoring

Like I mentioned, my program also needs to be small, therefore size will factor into the equation. So, to score your program:

  • Get the number of bytes, B
  • Run your code with the randomly-generated test cases provided by tests.py in this repo, and save the ref outputted.
  • Run your outputs through score.py, providing the ref at the start. The last input you will be asked for will be B.

Get the score outputted by score.py, and post it in your answer.

Sandbox

  • Is my background too long?
  • Is my scoring system too long-winded? I intend to use a complex algorithm (which I have mentally worked out, but not coded yet) which essentially creates a weighted average of all of the scores as a percentage of a value which is correct to 16 decimal places. Is referring people to some code, instead of telling them the algorithm, standard practice? I don't want to spend ages describing a confusing algorithm, when I could just write a program to do it.
  • Is this challenge not a duplicate? Is is unclear in any way?
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1
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Broken mouse

This is just an idea, I have not elaborated it.

My mouse accidentally fell to the ground, and now there is a double click for each of my single click(which makes window-closing very hard to do). :(

Most computer screens have a higher resolution ratio than 16x12, but let's assume that my computer screen has a 16x12 resolution ratio.

Example: A Window looks like this:

0-----OX
|      |
--------

The number 0 is the indicator of the window. O is a dragging button that allows windows to be moved. X is a closing button that closes the window. (You can not resize windows.) Assume that there is a window below that window looking like this:

1-----OX
|      |
--------

If I click X, I will close both windows. However, what should(or must, if appropriate) I do if I only want to close the first window?

I can move my mouse to the O tab and drag the window around by using mousedown. After 1 drag to the right:

10-----OX
||      |
---------

Now I can click the X to close the window 0 after I click the O button again to remove the dragging effect. (Note that there is the window "1" below that window.)

Wait, I changed my mind and wanted to close the window 1. What should I do?

I should click the number 1; then, the window 1 goes to the top and the X button shows. Now I can click the X button to close the 1 window.

For reference, this is the TUI commands I used(when the mouse starts at 0x0):

0-----O
>>>>>>.>.<<<<<<<.>>>>>>.

What should I do if I want to close the windows that I specified? (Output the TUI instructions.) (Your score is -(code length + output); you want to keep your score as high as possible.)

TUI Instructions

  • ^v<>: Move the mouse up, down, left, or right
  • .: Mouse down+mouse up (i.e. click)
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  • 3
    \$\begingroup\$ What does the input look like? \$\endgroup\$ – TheOnlyMrCat Aug 12 '19 at 21:35
  • \$\begingroup\$ I have no idea. \$\endgroup\$ – user85052 Aug 13 '19 at 4:36
  • \$\begingroup\$ Output for what (set of) input? \$\endgroup\$ – user202729 Aug 16 '19 at 4:49
  • \$\begingroup\$ @The Obviously a list of coordinates of the input windows... \$\endgroup\$ – user202729 Aug 16 '19 at 4:49
  • \$\begingroup\$ Is this always possible? If the frontmost window is as large as the screen, by dragging the "O" you cannot make the lower-leftmost cell appear. What if the "X" of the desired window is there? \$\endgroup\$ – user202729 Aug 16 '19 at 4:51
  • \$\begingroup\$ I guess I will make the windows draggable for at least 1 direction and at most 4 directions. (The window is always smaller than the screen.) \$\endgroup\$ – user85052 Aug 16 '19 at 4:59
  • \$\begingroup\$ Oh I see, otherwise output impossible to avoid this situation. \$\endgroup\$ – user85052 Aug 16 '19 at 7:00
1
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tags: "code-golf", "ellipse", "geometry"

Sandbox Questions

Is this a proper code-golf question?

A major challenge is: How to verify the computed shape? Numerical verification is impossible, since there are infinitely many possible solutions. Is there an easy way to plot xy-data online, or should I provide a script myself? Your suggestions are greatly appreciated.

edit:

after 3 days of being posted here in the sandbox, I still have no clear answer to the above question. I therefore propose to ask participants to include their own plot in the answer, which they can make with whatever plotting tool they wish. If people feel inclined to cheating, they only fool themselves, don't they?

Introduction

To create a circle you can stick a nail in a piece of board, put a loop of string around it and hold it taut with a pencil at the other end. Move the pencil and you get a circle. If you put the loop of string around two nails and move your pencil, you create an ellipse. But what happens if you use three nails, or four, or ten perhaps? It's gonna get ugly soon if you try this in real life, and that's where computers come in handy.

Challenge

Your task is to write a program or function that accepts two inputs:

  • A list of (x,y) coordinates (viz. the nails), of arbitrary length>2.
  • The length of the rope.

And produces the following output:

  • A list of coordinates of the poly-oval, which could be fed to a plotting-tool. Plotting the output does not need to be part of your program!

References

Details:

  • You may assume that the input coordinates form a convex shape (no inner points on which your program could crash).

  • As coordinates, you can use tuples, pairs, complex numbers or even two separate scalars if you like.

  • The output resolution (ie. the length of the list) is not so important, but is should give a fair representation of the real curve. In my experience, you'll need between 100 and 1000 points. For smaller rope lengths, you need an even higher resolution.

Rules and scoring:

  • This is code-golf, so shortest answer in bytes for each language wins.
  • Standard rules and default I/O rules apply.
  • Loopholes forbidden (of course).

Example Input and Output

Provide at least one example input and output. Make sure they match your own description of what the input should look like.

Input can be any of the following:

P = [2+0j, -2+1j, -2-1j]

P = [(2,0),(-2,1),(-2,-1)]

X = [2,-2,-2] and Y = [0,1,-1]

Output should be in one of the following forms:

[0.862+1.591j, 0.703+1.668j, 0.527+1.729j, ...]

[(0.862,1.591), (0.703,1.668), (0.527,1.729), ...]

X = [0.862, 0.703, 0.527, ...], Y = [1.591, 1.668, 1.729, ...]

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  • \$\begingroup\$ "You may assume that the input coordinates form a concave shape" I think you mean convex. This is a very helpful assumption though, as you would otherwise need to calculate the convex hull before doing anything interesting. \$\endgroup\$ – Beefster Aug 13 '19 at 22:05
  • 2
    \$\begingroup\$ "How to verify the computed shape?" - Two possibilities: 1. don't worry about it and make this a graphical output challenge ; 2. specify a starting angle and angle step and require accuracy to within 2 decimal points. ... I personally would go with #1 \$\endgroup\$ – Beefster Aug 13 '19 at 22:11
  • \$\begingroup\$ @Beefster Thank you, I did indeed mean convex. As per your second comment, frankly I am not interested in how to write short plotting code, I am interested in the calculation itself. But thanks a lot for your help, I think I will post in a couple of days:) \$\endgroup\$ – Hermen Aug 14 '19 at 16:28
  • \$\begingroup\$ One solution would be to specify a pixel resolution and require that the density of output points should be sufficient that the maximum separation between the curve and the piecewise linear output should be half a pixel. Then you can compare the output with the output of a reference implementation by looking for separations of more than one pixel. \$\endgroup\$ – Peter Taylor Aug 20 '19 at 15:55
1
\$\begingroup\$

I mainly need help with scoring as I want to encourage use of esolangs.

I also would like to know how to improve the answer-ability of this question in languages that don't specifically have defined functions


Church booleans

A church boolean is a function that returns x for true and y for false where x is the first argument to the function and y is the second argument to the function. Further functions can be composed from these functions which represent the and not or and xor logical operations.

Challange

Construct the church booleans and and not or and xor church gates in a language of your choice.

Scoring

The total length of all of the code required to make church true and false in your language and the and not or and xor church gates excluding the functions name. (for example, false=lambda x,y:y in python would be 12 bytes). You can reuse these names later in your code.

Pseudo code Examples:

true(x, y) -> x
false(x, y) -> y
and(true, true)(x, y) -> x
and(true, false)(x, y) -> y
# ... etc
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  • \$\begingroup\$ instead of functions, you should also accept full programs. I also don't understand what your examples represent(is and supposed to be a curried function?) \$\endgroup\$ – SuperStormer Aug 16 '19 at 20:43
  • \$\begingroup\$ @SuperStormer and returns a church boolean which is a function which is then called with variables x and y and returns x or y based on whether that function is the true or false church boolean. In the examples I was just trying to get across the nature of church gates and church booleans without answering the question. I wanted to break it up into discrete functions for readability and to ensure that the question is actually being answered correctly \$\endgroup\$ – Ryan Schaefer Aug 16 '19 at 20:46
  • \$\begingroup\$ I'm not really sure it's possible to make this work for all languages, except by just operating on lambda calculus expressions with no actual significance within the language, but that aside you definitely don't need anything additional to encourage esolangs on this site! \$\endgroup\$ – Unrelated String Aug 16 '19 at 20:55
  • 1
    \$\begingroup\$ @UnrelatedString as far as fit for this site goes do you think there is anything I should add to improve the question? \$\endgroup\$ – Ryan Schaefer Aug 16 '19 at 20:58
  • 2
    \$\begingroup\$ Esoteric languages usually don't support function as first-order object very well, but they usually have eval so it may work using some "function" representation. \$\endgroup\$ – user202729 Aug 17 '19 at 6:46
  • \$\begingroup\$ Otherwise I don't think there is a problem. \$\endgroup\$ – user202729 Aug 17 '19 at 6:46
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