Sandbox for Proposed Challenges

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Answer 1

Posted

Answer 2

post

Answer 3

Introduction

Book cipher

A Book cipher is a very unique method of a encipher. Here's how's it done:

• You have a book / a document or a article (something full of text, the more pages of text the better).
• You have a message to convey (a secret, of some sort)
• You simply-put read trough the text and the secret message (may come from input, or reading it from 2 separate files) - split it into words (so, separate spaces, commas and [dots]) so, ',' , '.' and spaces is the only requirement, how is not really that hugely important and you keep the count of how many words there are in the text, now input the secret message (note, the secret's words must be in the text, so if you secret was "My Secret" then, the words "My" and "Secrets" must both exist in the text.) and output the position of the inputted secret message. (E.g if the word "My" was nearly at the first page, maybe the 20th Word in the text, the program should print out '20'. Same with the word "Secrets", if that maybe were later, (let say the 93th word in the text) then your program should print out '93'.

Note the data type of input and output:

output numbers: Integers.

Input numbers: Integers

( Excluding if the secret actually contains a number, then it does not need to be treated as a int. Can be a plus if it does but is not necessary.)

Mini Example:

document.txt - file that contains text.

Secret: "My Secret"

(in the text, this is the 20th and the 93th word) (Note, this is only a made up secret, it is not from a real file, or a real input) a more better example is below.

Program input:

You enter "My Secret"

Program output:

20

93

And, again - you enter those numbers(**Integers**):

20 93

Program outputs:

My

Secret

this is just to show how input and outputs are related to each other.

For reference (if needed) You have a Python3 implementation available at my GitHub page, to see a book cipher in action here: GitHub - Book cipher in Py3

• Why is this challenge interesting?

I personally think this is a educational (and interesting) challenge ( one might also exercise, because of how simple it might seem to make, but really took myself - literally years to even know how to implement this correctly)

Interesting article to get some background of what Cicada3301 is (not my site) - https://www.clevcode.org/cicada-3301/

Wikipedia: Cicada3301

I created this challenge both to, see other peoples methods of solving this (you are free to use any programming language!) and also - how long it would take others (For me, really I think it took more than 4 years actually - even in Python3. It looks simple but, for me - really not)

• A motivating fact: There are still so little info (especially on example codes) on the internet(at least by the time writing this challenge) about just, book cipher implementations

Challenge

I would highly suggest making dedicated functions for this challenge

• (instead of writing all code in the main() function - but it's totally fine to have it all in main!)

Operation:

Here's how the program should read, process, and output the result:

First, take the text (the book/document, with the lots of text, (not the secret)) and:

Note: The text can either be entered or read from a file. You choose this.

1. read it (From a file, or enter it as input)
2. split it into words (by, I.e detecting '.', spaces(' '), and commas ',') (Or if you already have split the input & are ready to move on to step 3, do that :) )
3. count the number of words.

Repeat this process with the Secret input part.

So, the input secret part should be:

• read it (from, again a file or enter it as input)
• split it (i.e if your input was "My Secret" - split it into words like so: "My" "Secret")

My Python3 implementation only separate spaces.

The Key sequence - this is the nth words your text contains, e.g the 93th word in above example "Secrets".

The winner will be chosen by how short the code is. (So, the shortest code = win)

Example Input and Output

example file used 'document1.txt'in this section is available at the GitHub page. as well as the Python3 file used in the example below.

The output of your program should match the output of the Python3 program.

Input:

python3 bookcipher.py

input text: a house with a Bob inside

Output:

you entered these words: ['a', 'house', 'with', 'a', 'Bob', 'inside']

2

3

5

2

0

30

Input again: (decrypting)

input key-sequence sep. With spaces: 2 3 5 2 0 30

a

house

with

a

Bob

inside

Answer 4

Subbasis. Generate. Discrete?

Objective

Given finitely many finite sets, interpret them as a subbasis to generate a space, and decide whether the resulting topology is discrete.

Introduction to Topology

Given a set \$X\$, a topology \$\mathcal{T}\$ over \$X\$ is a subset of the power set \$\mathcal{P}(X)\$ such that:

• \$\emptyset, X \in \mathcal{T}\$.

• For all \$\space \mathcal{U} \subset \mathcal{T}\$, \$\bigcup\mathcal{U} \in \mathcal{T}\$.

• For all \$Y_1, Y_2 \in \mathcal{T}\$, \$Y_1 \cap Y_2 \in \mathcal{T}\$.

Members of a topology are said to be open. So the rules above in plaintext are:

• The empty set and \$X\$ itself are open.

• The union of arbitrarily many open sets is open.

• The intersection of finitely many open sets is open.

Endowed with a topology, \$X\$ is said to be a (topological) space.

If \$\mathcal{T} = \mathcal{P}(X)\$, \$\mathcal{T}\$ is said to be discrete.

Basis and Subbasis

A subset \$\mathcal{B}\$ of the power set \$\mathcal{P}(X)\$ is said to be a basis (pl. bases) of a set \$X\$ if:

• For all \$x \in X\$, there exists \$B \in \mathcal{B}\$ such that \$x \in B\$.

• For all \$B_1, B_2 \in \mathcal{B}\$, there exists \$C \in \mathcal{B}\$ such that \$C \subset B_1 \cap B_2\$.

We take every subset \$\mathcal{U} \subset \mathcal{B}\$ and declare \$\bigcup\mathcal{U}\$ to be open to generate a topology \$\mathcal{T}\$. Note that \$\mathcal{B} \subset \mathcal{T}\$ always holds.

If we omit the second requirement, we have a subbasis of \$X\$. A subbasis generates a topology by also declaring the intersection of finitely many members to be open.

Input and Output

Given a set of finitely many finite sets \$\mathcal{S}\$, \$X\$ shall be implicitly defined as \$\bigcup\mathcal{S}\$. Note that by this, the first requirement for bases always holds.

The input/output format is flexible. In every case, inputs that don't fit in your input format fall in don't care situation.

Examples

Truthy

• \$\emptyset\$ (Generates \$X = \emptyset\$ and \$\mathcal{T} = \{\emptyset\}\$)

• \$\{\emptyset\}\$ (Ditto)

• \$\{\{0\}\}\$ (Generates \$X = \{0\}\$ and \$\mathcal{T} = \{\emptyset, \{0\}\}\$)

• \$\{\emptyset,\{0\}\}\$ (Ditto)

• \$\{\{1\}\}\$ (Generates \$X = \{1\}\$ and \$\mathcal{T} = \{\emptyset, \{1\}\}\$)

• \$\{\{0\},\{1\}\}\$ (Generates \$X = \{0,1\}\$ and \$\mathcal{T} = \{\emptyset, \{0\},\{1\},\{0,1\}\}\$)

• \$\{\{0\},\{1\},\{0,1\}\}\$ (Ditto)

• \$\{\{0\},\{1\},\{2\}\}\$ (Generates \$X = \{0,1,2\}\$ and \$\mathcal{T} = \{\emptyset, \{0\},\{1\},\{2\},\{0,1\},\{0,2\},\{1,2\},\{0,1,2\}\}\$)

• \$\{\{0,1\},\{0,2\},\{1,2\}\}\$ (Ditto)

Falsy

• \$\{\{0,1\}\}\$ (Generates \$X = \{0,1\}\$ and \$\mathcal{T} = \{\emptyset,\{0,1\}\}\$)

• \$\{\{0,1\},\{1\}\}\$ (Generates \$X = \{0,1\}\$ and \$\mathcal{T} = \{\emptyset,\{1\},\{0,1\}\}\$)

• \$\{\{0\},\{1,2\}\}\$ (Generates \$X = \{0,1,2\}\$ and \$\mathcal{T} = \{\emptyset, \{0\},\{1,2\},\{0,1,2\}\}\$)

• \$\{\{0,1\},\{1\},\{2\}\}\$ (Generates \$X = \{0,1,2\}\$ and \$\mathcal{T} = \{\emptyset, \{1\},\{2\},\{0,1\},\{1,2\},\{0,1,2\}\}\$)

Answer 5

Decode an 8086 MOD R/M

code-golfbitwiseparsing

I think this might be fun. Or, it might be torture, idk. 😛 If this is popular, I might add a sequel for the significantly more complex 32-bit encoding 😏

Time for a mini objdump.

An 8086 MOD R/M field is laid out like so:

MOD  REG  R/M |  OPTIONAL DISPLACEMENTS
mm   rrr  rrm | (iiiiiiii) | (iiiiiiii)
76   543  210 |  76543210  |  76543210

REG is a register. Quite unintuitively, the register names are not in alphabetical order.

Note that you can safely assume a word register, not a half byte register, and that the destination is a register.

REG |  0 |  1 |  2 |  3 |  4 |  5 |  6 |  7 |
Name| AX | CX | DX | BX | SP | BP | SI | DI |

MOD determines the length and format of the instruction.

MOD | FORMAT
 0  | [MEM] or [ADDR]
 1  | [MEM+/-disp8] (signed 8-bit immediate)
 2  | [MEM+/-disp16] (signed 16-bit little endian immediate)
 3  | REG

MEM is parsed as so:

MEM  |    0    |    1    |    2    |    3    |   4  |   5  |   6   |   7  |
Name | [BX+SI] | [BX+DI] | [BP+SI] | [BP+DI] | [SI] | [DI] | [BP]* | [BX] |
*when MOD==0, [BP] is replaced by an absolute 16-bit address.

Just [BP] is encoded as [BP+0].

I am going to represent MOD R/M as octal, and addresses/displacements as hex. It really bugs me how few people write it this way, as it makes much more sense.

So, for example:

MOD  r  r/m
 3   0    0
reg  |    |
    AX,  AX

 0   2    0
mem  |    |
    DX,[BX+SI]

 1   3   7 , 23
M+D8 |   |   |
    BX, [BX+0x23]

 2   2   1 , BC 6A
M+D16|   |    | /
    DX,[BX+DI+0x6ABC]

Rules:

• You may take your input as a packed integer, byte array, string in any mix of bases, or whatever. I'm not picky. I personally wrote them as mixed hex and octal.
• You will always get 3 bytes, however, in true objdump spirit, those extra bytes will be random. The first byte is all you need to determine the length.
• Not all cases will be the most efficient encoding.
• In the output:
  • It may be returned as a single string, or printed.
  • It is case insensitive
  • It can have excess spaces or tabs, but it must be on one line.
  • It can have an optional trailing newline
  • Displacements and addresses can be in any base, however, do note that displacements are signed two's complement and will be subtracted if negative. So, for 100 FF, AX,[BX+SI+0xFF] is wrong.
  • Leading zeroes and displacements of zero are fine.

Test cases (irrelevant bytes are in italics):

300 73 A2 -> AX,AX
312 01 82 -> CX,DX
337 3E 1C -> BX,DI
020 24 AF -> DX,[BX+SI]
137 23 6B -> BX,[BX+0x23]
066 34 21 -> SI,[0x1234]
166 00 10 -> SI,[BP+0x00]
221 BC 6A -> DX,[BX+DI+0x6ABC]
124 FF EF -> CX,[SI-0x01]
224 FF FF -> CX,[SI-0x0001]
240 00 00 -> SP,[BX+SI+0x0000]

Answer 6

Create a QR quine

(a "qruine" if you will)

Design a QR code that legibly spells with its pixels (or the space between them) the text that it scans to.

For example, this QR code scans to the letter A, and also spells out A in white:

It does not matter what the scanned and displayed text is; it does not have to be coherent or readable.

The winner is the person with the longest text.

Answer 7

Posted link

Answer 8

Is this code in the same language as my answer? (WIP)

Probably a bad idea, but the goal here is to output a truthy value if a given input string is valid syntax in the same language as your answer.

Answer 9

I don't care how it started, but I'm going to end it!

kolmogorov-complexity

---

Given a number between 0 and 10,000 (inclusive) as input, output that many arbitrary* printable ASCII characters, followed by the exact text:

I don't care how it started, but I'm going to end it!

_{* The arbitrary preceding text must not contain the ending text.}

You do not need to verify the input value.

Answer 10

Shortest and Asymptotically Fastest Sort of 3-Tuples

Tags: fastest-algorithmcode-golfsorting

Write the shortest and asymptotically fastest function or program that will sort a set of 3-tuples.

Input

Input is a set (or unique list, array, etc) of 3-tuples, containing positive integers.

Output

Output is a set (or unique list, array, etc) of 3-tuples sorted in the following way:

• The first elements of each tuple are monotonically increasing.
• For each value of the first elements, the second elements are monotonically increasing.
• For each value of the second elements, the third elements are monotonically increasing.

Additional Rules

• As well as a byte count, include the asymptotic time complexity spent by your program.
• Explanations are encouraged! (Especially for showing the time complexity)
• Standard loopholes are forbidden.
• Input and output is flexible, as long as each 3-tuple is individually identifiable.
• Scoring is time complexity, with byte length as a tie breaker.

Examples

Input - Output # Comment
[(1,2,3), (400,500,600), (0,0,0)] - [(0,0,0), (1,2,3), (400,500,600)]
[(1,0,255), (1,255,0), (1,10,123), (1,50,96)]
 - [(1,0,255), (1,10,123), (1,50,96), (1,255,0)] # sorted by second elements
[(1,0,255), (1,0,0), (1,0,123), (1,0,96)]
 - [(1,0,0), (1,0,96), (1,0,123), (1,0,255)] # sorted by third elements
[(1,0,255), (1,255,0), (1,10,123), (1,50,96), (2,0,255), (2,0,0), (2,0,123), (2,0,96)]
 - [(1,0,255), (1,10,123), (1,50,96), (1,255,0), (2,0,0), (2,0,96), (2,0,123), (2,0,255)] # sorting by first and second
[(1,0,255), (1,255,0), (255,23,232), (1,10,123), (1,50,96), (2,0,255), (2,0,0), (2,0,123), (2,0,96), (1,2,3), (400,500,600), (0,0,0)]
 - [(0,0,0), (1,0,255), (1,2,3), (1,10,123), (1,50,96), (1,255,0), (2,0,0), (2,0,96), (2,0,123), (2,0,255), (400,500,600), (255,23,232)]

Answer 11

First sequence with no square differences

Answer 12

Lists of power

code-golf kolmogorov-complexity

Generate the following list of lists.

[[0], [1], [2, 4, 8, 6], [3, 9, 7, 1], [4, 6], [5], [6], [7, 9, 3, 1], [8, 4, 2, 6], [9, 1]]

This is code-golf, so shortest answer (as measured in bytes) wins.

Answer 13

Sequential Multiplication Magic Squares

code-golf

(Inspired by this question for a 5x5 and this question for a 4x4 magic square on the Puzzling SE sites.)

For this challenge, a sequential multiplication magic square is an NxN square filled with numbers 1..N² where the product of any M-th row equals the product of the M-th column. That is, the product of the first row is equal to the product of the first column, the product of the second row is equal to the product of the second column etc.

For example, one such 3x3 square might be as follows, but other similar results are valid as well:

9 8 3
4 5 2
6 1 7

Notably, there is no such square for N=2.

Challenge

Given a side size N of 1 or larger, output a valid NxN sequential multiplication magic square, or any distinct falsy value if none exists.

Standard loopholes apply, any convenient input-output, this is code-golf so the shortest code in bytes wins.

Sample cases

1 → [1]

2 → any distinct falsy value

3 → [[9, 8, 3],
     [4, 5, 2],
     [6, 1, 7]]

4 → [[16,  3, 12,  4],
     [ 9, 10, 14,  1],
     [ 8,  7, 11, 15],
     [ 2,  6,  5, 13]]

5 → [[ 7, 16,  6,  3, 25],
     [ 5, 13, 22, 12, 24],
     [ 9, 11, 17, 14,  4],
     [20, 18, 21, 19,  1],
     [ 8, 10,  2, 15, 23]]

Answer 14

Three, Three, No

Answer 15

Syslog PRI Conversion

This is my first CodeGolf post, so I expect some errors my content.

The rsyslogd utility has been a tool used throughout time to handle and parse logs either over an IP network or even locally. As many of you might know, this tool utilizes the basic syslog protocol.

The syslog protocol handles both a Facility and a Severity level in one integer, called Priority. The formula to extract these levels is as follows:

Priority = Facility * 8 + Level

In this challenge, your task is to write an application that converts a Priority value from the syslog protocol into a human readable format. The application must take input from STDIN, and output both the Severity and Facility string associated with the numerical code.

The numerical code/type table is as follows:

Int     Severity
0       Emergency
1       Alert
2       Critical
3       Error
4       Warning
5       Notice
6       Informational
7       Debug

Int     Facility
0       kernel messages
1       user-level messages
2       mail system
3       system daemons
4       security/authorization messages
5       internal
6       line printer subsystem
7       network news subsystem
8       UUCP subsystem
9       clock daemon
10      security/authorization messages
11      FTP daemon
12      NTP subsystem
13      log audit
14      log alert
15      clock daemon
16      local0
17      local1
18      local2
19      local3
20      local4
21      local5
22      local6
23      local7

The format of the outputted text may be any style you like, as long as it retains its human readable characteristics.

Examples

mail system, Critical\n

mail system\n
Critical\n

mail system - Critical\n

mail system Critical\n

Example

Given a PRI value of 103, your program must output:

NTP Subsystem, Debug

The shortest answer in bytes wins!

Answer 16

SSD optimize

Given \$n\$ pages, each page containing \$m\$ sectors, write three functions: (Here x and y are sectors)

1. insert(x) that stores the input(temporary sector) into a sector,
2. remove(x) that removes one, and
3. get(x) that return a sector containing the element.

You can call these functions:

1. copy(y,x) that copy a sector from x to y, and
2. clear(x) that clears the page containing x, can only be called \$k\$ times for each page.

There'll never be more than(can equal to) \$p\%mn\$ elements required to store. Your score is the numbers of call before you fail. Everyone can provide test case for any program.

\$n=256, m=16, p=75, k=100\$.

For example, if a solution don't do any clear and just place inputs into \$(1,1), (1,2), \cdots, (n,m)\$, someone else can write and remove till you use up all space:

insert\*3072, (delete, insert)*1025, get

The last get can't get anything and is a fail, so the score is 5122.

Highest score wins. Robber's winning criticia TODO.

Answer 17

Build a Markdown to HTML converter

code-golf string
The Stack Exchange network uses Markdown as the syntax for writing posts. For example, using a # at the beginning of a line creates a heading (<h1>) while two hashes ## creates a subheading (<h2>).
Your task is to write a program which takes input as a syntactically valid Markdown string and outputs its HTML equivalent. (This program might find use as a means to transfer SE posts to one's own website.)
The only Markdown "commands" you need to support are the backtick (becomes a tag named code, styling provided), the hashes (# becomes h1, ## becomes h2 and ### becomes h3), and the > (blockquote). The rest may be left intact.

For example, if the input is

# Some text
## Part 1
Lorem `ipsum` dolor sit amet
> consectetur adispicing

Then the output should be

<h1>Some text</h1>
<h2>Part 1</h1>
Lorem <code>ipsum</code> dolor sit amet
<blockquote>consectetur adispicing</blockquote>

Leading spaces are acceptable for the headings as they are mandatory in Markdown, but trailing spaces are not (you may assume the input has no trailing spaces). Except for the inline code, all commands will be displayed as blocks and will be on separate lines. For example

# Some text ## Another

is not a valid input because there is a block command on the same line as another block command. You may assume that the input contains no < or > except for blockquote notation, you must also follow the guidelines exactly, so no outputting HTML which renders the same result but in a different way.

Second test case:

### Subheading
> This is some heading with `code` in it.

becomes

<h3>Subheading</h3>
<blockquote>This is some heading with <code>code</code> in it.</blockquote>

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

Answer 18

Output a random pair of twin primes. Every pair should possibly appear and the program should have zero possibility to fall into infinite loop. Notice that we don't know if there are infinite many pairs so you need some fallbacks to avoid finding a not-existing pair.

Answer 19

Finding Distant Primes

Answer 20

Add trailing whitespace code-golf

Sometimes, we accidentally have trailing whitespace in test cases, and some helpful person notices and fixes that. Thank you, helpful people.

But what if we want to take a string without trailing whitespace and add some?

Your challenge is to write a program that takes a string as input and adds between 1 and 10 spaces (randomly) to the end of each line.

Rules

Between 1 and 10 (inclusive) spaces (" ") must be added to each line. There must be a nonzero chance of getting any number of spaces on any line.

This is code-golf, shortest wins.

Apologies if this already exists - It's really hard to search.

Answer 21

2D Pathfinding with Momentum

Posted to main

Answer 22

Posted

Answer 23

Count What You See code-golfnumbersequence

You may have heard of the Look-and-say sequence, which is generated by reading off the digits of previous entries in the sequence. Here, you will be tasked to generate the "Count-and-say sequence".

In general, the sequence can be generated as follows:

1. Start with an arbitrary sequence of numbers (e.g. 1, 1, 1, 3, 2, 1, 2).
2. Count the occurrences of each number as adjective noun pairs -> "four 1, one 3, two 2", in order of 1st appearance. In the example, this means that you must first count 1s, then 3s, then 2s, since that is the order in which the numbers first appear in the sequence.
3. Write out the result from step 2 numerically ("four 1, one 3, two 2" -> 4, 1, 1, 3, 2, 2).
4. Append the result from step 3 to the original sequence to get 1, 1, 1, 3, 2, 1, 2, 4, 1, 1, 3, 2, 2.
5. Repeat the steps above to continue the sequence.

Task

Your task is to output the "Count-and-say sequence", such that the sequence starts with 1. You may choose to:

• Take an input \$ n \$ and output the first \$ n \$ integers.
• Take an input \$ n \$ and output the \$ n \$-th integer.
• Output the sequence indefinitely.

For convenience, here are the first 100 numbers in the sequence (also A217780):

1, 1, 1, 3, 1, 4, 1, 1, 3, 6, 1, 2, 3, 1, 4, 8, 1, 3, 3, 2, 4, 1, 6, 1, 2, 11, 1, 5, 3, 3, 4, 2, 6, 3, 2, 1, 8, 13, 1, 8, 3, 4, 4, 3, 6, 5, 2, 2, 8, 1, 11, 1, 5, 16, 1, 10, 3, 6, 4, 4, 6, 7, 2, 4, 8, 2, 11, 3, 5, 1, 13, 18, 1, 12, 3, 9, 4, 6, 6, 9, 2, 5, 8, 3, 11, 4, 5, 2, 13, 1, 16, 1, 10, 1, 7, 22, 1, 14, 3, 11

Answer 24

Equalizing fractions

Answer 25

Node one-liner to fetch a URL, like curl

I'm interested in the shortest one-liner to output the contents at a given URL, using Node.js from the command line, for practical purposes. In other words, the equivalent of curl, written as a Node one-liner.

Not interested in other languages. Would this respect the site's rules, or does it belong on SO?

Rules:

1. The URL is passed via the command line, so accessed via process.argv[1]
2. Must invoke node with the -e argument, followed by the code, followed by the URL
3. Only the length of the actual script passed to node via -e "..." is counted.

My best solution so far, with http://x.com as a conveniently short example, is:

node -r got -e "require('got')(process.argv[1]).then(r=>console.log(r.body))" http://x.com

Answer 26

Program-Write a program to display repeating terms of a given sentence.

Explanation-the program must output the repeating terms of two or more letters from the given input(input is a sentence seperated be spaces without any punctuation except the full-stop indicating the end.) For example, if input is the sentence "I am an ameture mathemagician" the outupt must be am, ma, an. ( not that em is not a valid output as it is separated by space)

Example-

input->International competitions are better than intercollege ones.

output-> Inter, ti, er, tion, io,on,ion, tio, co, on,.......etc (t, l must not be included as they are 1 letter.) (Upper lower Cases do not matter)

Test cases-

input-> aabcde cdec

output-> cde, cd, de

input-> aab aacab

output-> aa, ab

input-> aaa aabcaaa ababa

output-> aaa, aa, ab, aba, ba

Winning Criterion:- code golf

Answer 27

Getting to the root of the problem

While I was sleeping in my bed, unwilling to wake up, an idea entered my head: why is the syntax for powers, especially roots, so cumbersome? It would save so many bytes if we could just use the square root symbol instead, and easier to understand too. So, your challenge is to encode this in whatever format you choose, in as few bytes possible.

Answers should be able to:

a) convert a string such as 2**(1/2) into √2 or some other format that distinguishes it from 2√2 (note, if you choose to write 2√2 as 2 * √2 and write things like 2**(1/3) as 3√2, that is allowed).

b) Work for arbitrary powers (2**(1/50) should work fine).

c) Simplify roots. (4**(1/4) = √2)

and should be able to perform this on inputted strings.

Deduct 10% from your score if you can handle addition of roots, deduct a further 10% off that if you can handle the ret of the basic operators (-, *, /), another 10% if you can simplify expressions such as (2 - √2)/(2 + √2), another 10% if you can write 16**1/4 (for example) as √(2^2), and, if you're amazing enough to implement exponentiation, you can subtract 50%.

Input will be presented in the form of [0-9]**([0-9]/[0-9]), where the 0-9s can be any number of digits. Output should ideally be in the form of [0-9] * [0-9]√[0-9], again, with the 0-9s being any number of digits, but I will let other forms slide so long as as 3√2 (that's the cube root of 2) is distinguishable from 3 * √2.

Tags: code-golfnumbermath

Lowest score wins. Good luck!

Answer 28

Computer Tree

Consider an infinite amount of same computers building a tree, running same program. Each computer has infinite memory and infinite pins 0 to Infinity, where pin 0 connect to its parent, or the IO we see for the root; and pin 1..Inf connect to its childs.

Each connection is bidirectional, and has buffer in each direction. Writer put the value into buffer, and reader gets from it.

The computers need to support these abilities: (Here dest is a variable in the memory, and src1, src2 are either variable or immediate integers. [x] mean the memory in address x.

dest = src1 op src2, op in +,-,*
[dest] = src1
dest = [src1]
if(src1 op src2) goto inst, op in <,==,<=,!=
if((not)pin src1 writing) goto inst
if((not)pin src1 reading) goto inst
write src2 to pin src1, block if already writing
read dest from pin src1, block if not reading

It's fine if you need several elements to do one job above, but each job defined above should use same amount of time(In this model timing matters). It's also fine if you take input as some other formats, but to avoid taking too ready functions, an same-type input shouldn't lead to an infinite loop. Input for root is given when started and will never need to wait unless all input used up, but it doesn't always halt.

Shortest code win.

Answer 29

Tags: code-golfunicodestringconversion

Interpret a Cangjie Input Method String

The Cangjie input method is a method for inputting Chinese characters using a standard QWERTY-like keyboard. Each Chinese character is encoded as a sequence of Latin letters, each letter representing a radical, or part, of the character's form. Each letter encodes both the radical character it represents, as well as other, related radicals (such as E encoding 水 as well as 氵, and more).

There are 24 radicals encoded in Cangjie, as well as 3 other characters for wild cards and other purposes. For the purposes of this challenge, only the subset of the main 4 groups are used, shown below with meanings:

Philosophical group
A   日 sun
B   月 moon
C   金 gold
D   木 wood
E   水 water
F   火 fire
G   土 land

Stroke group
H   竹 bamboo
I   戈 dagger axe
J   十 ten
K   大 big
L   中 centre
M   一 one
N   弓 bow

Body parts group
O   人 person
P   心 heart
Q   手 hand
R   口 mouth

Character shapes group
S   尸 corpse
T   廿 twenty
U   山 mountain
V   女 woman
W   田 field
Y   卜 fortune telling

Cangjie Basic Rules

Characters are analyzed as such to create a Cangjie code (based on the Wikipedia article above):

• Direction of decomposition: left to right, top to bottom, outside to inside
• Geometrically connected forms: takes 4 Cangjie codes from the 1st code to the last code
• Geometrically unconnected forms:
• • Forms in exactly 2 subforms: Follow the direction of decomposition rules, then take the first and last codes of of the first subform, and the first, second, and last code of the second subform.
• • Forms in more than 2 subforms: take the first and last codes of the first subform according to direction of decomposition, then break the remainder into subforms. Take the first and last codes of the first remainder, and the last code of the last remainder.

The Challenge

Write a full program or function that, when given a valid Cangjie code string as input, outputs its corresponding traditional Chinese character.

Additional Rules

• Use Cangjie version 5.
• Standard loopholes are forbidden.
• An invalid Cangjie code string (not in our subset of codes) is undefined behavior when used as input.
• If multiple characters match a Cangjie code string, you can choose to output both, or choose one. If you choose one, it must only output that character when given that code.
• This is code-golf, so shortest code wins!

Examples

Input - Output (notes)
JWJ - 車 (connected, top to bottom: 十田十)
YRHHI - 謝 (3 parts: first is disconnected, take first and last YR;
           second is is disconnected, take first and last HH; last part take last I)
AN - 門 (special case: fixed decomposition)
OMN - 气 (another fixed decomposition; using version 5)
A - 日
BOB - 肭
JPHI - 蜜
GUMPC - 顤
STKR - 匿 or 𡲢 (if multiple characters exist for that code, pick one deterministically)
HXH - (undefined behavior, since X is not in the set of codes above)

Meta

• Is it clear? Anything that needs adding/removing?
• Any weird test cases I didn't put in?
• Anything else?

Answer 30

Text in aLtErNaTiNg cApS

Sometimes, we want to convey sarcasm in a text message or in a YouTube/Reddit comment. To this end, "alternating caps" is often used. Your task, should you wish to accept it, is to write code that turns the input text into its "alternating caps" version.

(This is a deleted rule. You should ignore this for the challenge) For most sans-serif web fonts, it is hard to distinguish capital I (for India) and lower-case l (for Lima). So we want to avoid either of these letters in our output. To achieve this, we are allowed to sacrifice "exact alternating-ness" of the output. Details below.

Input:

1. A string of words involving [a-zA-Z], with one space in between each word.
2. You may not assume whether or not the string ends with a space/newline/etc.

Output:

1. The input, turned into "alternating caps form", with the first letter of each word being lower-case.

2. (Deleted; you should not implement it. I have included it just to illustrate my thought process) You may not output any capital I (I, for India) or lower-case l (l, for Lima). To avoid these, you may continue outputting the same letter-case as the previous letter, but you must switch the letter-case at the earliest possible instance. (note to self: this requirement means there are sometimes more than two letters of the same case, which I don't really want)

3. Non-suppressible output can be ignored.

Rules:

1. Standard loopholes are forbidden.
2. You must take input from and output to natural places, according to your language.
3. This is code-golf, so the lowest byte-count wins. Ties are broken by earliest submission.
4. Please provide a way for readers to test your code (e.g. TIO).
5. An ungolfed version and an explanation for your code is appreciated, although not required for the challenge.

Examples

Input -> Output
---------------
alternating -> aLtErNaTiNg
lower case letters -> lOwEr cAsE lEtTeRs

Examples that follow the deleted rule (which you should not implement -- these are just for your interest:

I used dcode to find some of these examples. holding -> hOLdiNg radii -> rAdii (has more than 2 lower-cases in a row, if using my rules) fall -> fALL (has more than 2 capitals in a row, if using my rules) volleyball -> [even if you are allowed to change the previous letter-cases to try to stop 'ALL' (3 capitals in a row) from appearing, there is a non-unique way of doing so]

Good luck!