Sandbox for Proposed Challenges

Question

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

Sandbox FAQ

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The purpose of the sandbox is to give and receive feedback on posts. If you want to, feel free to give feedback to any posts you see here. Important things to comment about can include:

• Parts of the challenge you found unclear
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Answer 1

Shuffle a subsequence

Answer 2

Pluralize a Noun List

Currently Closed

Answer 3

Minimal Randomness

In this challenge, you take input and shuffle the letters in a random, non-deterministic way which minimizes the probability that the output is different from the input.

Rules

1. Your program must take input and use only substitution and transposition to randomly modify the input.

2. There must be a slight, non-zero probability that the output differs from the input.

3. Your program is graded based on the probability of its output differing from the input, with a lower probability being better.

4. If two programs are tied in score, the tie is settled by the code size, with a shorter code being better.

5. Your program must be non-deterministic.

Meta

I'll post this to main soon unless there are any issues with it.

Answer 4

Short programs for fixed outputs

^{Inspired by Lynn's Jelly puzzles. Check them out if you're interested in practicing your Jelly skills}

Cops

The cops should choose three things:

• A freely available programming language,
• a byte count \$B\$, and
• a number of programs to write, \$n\$ (minimum 5)

They should then write \$n\$ programs, each of which:

• is exactly \$B\$ bytes long, and

• outputs a fixed, non-empty, non-whitespace output. That is, the output should contain at least one non-whitespace character. "Fixed" can mean that either:

  • it outputs the same thing no matter what input is provided, or
  • that it always outputs the same thing and takes no input.

  You may choose which of these meanings to take, but it must be the same for all \$n\$ programs. Please mention which of these options your programs use.

The cops should then reveal the following bits of information:

• The programming language used,
• the byte count \$B\$,
• any command line flags used for specific outputs,
• the \$n\$ outputs for each of the \$n\$ programs. If the outputs use any non-printable ASCII characters, please include a hexdump of the output.

The Robbers will be attempting to find \$B\$ byte long programs that output the same outputs, so you should keep your programs secret.

For example, if you choose to write 7 programs in Python, each of them 10 bytes, that output

4, True, 2 3 , 1, 72, ! and [0]

then you may have these 7 programs (one per line).

Robbers will crack one of your \$n\$ outputs if they can find any \$B\$ byte program in your language that has the same output. Note that the program does not have to be the same as the cop's program.

Any outputs that go a week without being cracked can be marked safe, and the programs for each output should be revealed. Until the program is revealed for a specific output, it can still be cracked.

You may post multiple answers, but each answer should be independent from all others. Your score is equal to the total number of safe outputs across all your answers. The user with the highest score wins.

Robbers

You should find a Cops answer with at least one uncracked, unsafe output, and attempt to crack any of the outputs. That is, find a program that is exactly \$B\$ bytes long that outputs the same fixed output. Note that your program does not have to be the same as the Cop's original answer, just that the output has to be equal.

If you crack an answer, please do the following:

• Leave a comment on the Cop's answer, linking to either your answer or a TIO (or similar) link demonstrating the crack
• If this is your first crack, post an answer to the Robbers thread with your crack, linking to the relevant Cop answer
• For further cracks, edit them in to your existing answer, linking to the relevant Cop answer

A Robber's score is equal to the total number of cracks they make. The Robber with the highest score wins.

---

Meta

• Thoughts? Feedback?
• Tags are cops-and-robbers, code-shuffleboard, kolmogorov-complexity. Any others?
• Is this a duplicate?

Answer 5

Cell Evolution

Your lab needed to simulate how a particular cell evolves over time in a 2D grid space. A sample 2D grid space below shows a single cell at the centre of the grid.

0 0 0 0 0
0 0 0 0 0
0 0 1 0 0
0 0 0 0 0
0 0 0 0 0

The cell evolution follows these rules:

1. '0' indicates no live cell
2. A positive number indicates a live cell. The number indicates its age.
3. A cell will grow from age 1 to 5 in each evolution
4. After age 5, a cell will die at the next evolution (resetting to '0')
5. If a cell has 4 or more neighbours (adjacent and diagonally), it will die due to over-crowding.
6. In each evolution, a live cell will spread to its neighbour (adjacent and diagonally) if there is no live cell there and that neighbour is not overcrowded (surrounded by less than 4 cells)

Given an integer n in the input, which represents the size of the grid given, output the next generation of cells until all cells are dead ("0")

Extra rules:

1. The first live cell is always in the center of the grid
2. n must be odd so the live cell is always centered
3. The grid size <=9 to prevent incredibly large outputs of data

Test case

Only 1 to save space in question

Input: 3

0 0 0
0 1 0
0 0 0

1 1 1
1 2 1
1 1 1

2 0 2
0 0 0
2 0 2

3 1 3
1 1 1
3 1 3

4 0 4
0 0 0
4 0 4

5 1 5
1 1 1
5 1 5

0 0 0
0 0 0
0 0 0

This is code-golf, so shortest bytes wins!

Tags:

matrix

code-golf

ascii-art

cellular-automata

Please check the tags or edit them if they're wrong or you think a particular tag is not here. Feel free to comment on this puzzle!

Answer 6

From code to golf (Cops and Robbers)

Answer 7

Navigate the city

The government of your country has just completed a city designed to accommodate a few hundred thousand people. It has all sorts of facilities including roads, restaurants, malls, houses, etc. You have been invited to test the road system, but you are completely unfamiliar with it, so you need a GPS. Your challenge is to make one.

Description of the city

Note: when I say "a x a grid", I mean that there are a horizontal roads and a vertical roads within the grid.

To make the challenge easier (because of course making a GPS is difficult in itself), the city is fixed. The city's road system is based on a very rigid grid. This grid is pictured further below.

The grid has a size of 15x15 and the roads are labeled as [r/c num][dir] where "r/c num" is the row/column number (whether it is a row or column depends on the direction of the road) and "dir" is the direction. If the road runs from west to east, "dir" is E, and if it runs from north to south, "dir" is S. For instance, "1E" is the first row of the grid, while "12S" is the twelfth column of the grid. Each row and column of the grid has a length of 14km (1km between each intersection).

The Central Business District (CBD) is the 5x5 sub-grid situated in the middle of the grid. Due to the traffic parameters set below, it is important for your GPS to route the user away from the CBD if it is not necessary to pass through that district. Note that the CBD includes the borders of the 5x5 sub-grid.

At each intersection, there is a traffic light. The amount of time to wait is as follows:

• there is a "base time" which is 400 if the intersection is in the CBD, and is the row position of the intersection (row 1 column 2 would be the intersection between 1E and 2S) times the column position otherwise;
• the waiting time to turn left is equal to the base time;
• the waiting time to go straight is equal to the base time, multiplied by 2;
• the waiting time to turn right is equal to the base time, multiplied by 3.

The times above are measured in seconds.

In addition to the standard grid of roads, there is an expressway circling the inner part of the city. It passes directly over parts of the 4E, 4S, 12E and 12S roads in such a way that it forms a square. In both directions, there is an innovative exit/entry elevator at each place where there would be an intersection if you took the 4E, 4S, 12E or 12S road rather than the expressway. It is positioned in such a way that you can skip the traffic light for that intersection and get going, and in addition to that you can turn your car around in whichever direction you would like and go that way. I know it sounds rather confusing, but in essence you can exit at any intersection and go whichever way you wish, with the distances still being measured in kilometers in all cases. Note that the elevator is instantaneous (once again, not very realistic, but who uses elevators for cars on the main road anyway?). Upon entering the expressway, you can go in either direction. On the expressway, there are no at-grade intersections, so the traffic is free-flowing, and there are no waits at traffic lights or any other obstruction. Entry onto the expressway is done at any intersection involving the 4E, 4S, 12E or 12S road. Cars entering the expressway do not need to wait at a traffic light before doing so. Once again, the way in which the entry elevator is designed ensures that all distances are still measured in kilometers. This means that you can drive 1km from an intersection, enter the expressway there, and drive 3km on the expressway, with the total distance being 4km.

The city sets speed limits as follows:

• 30 for all roads within the CBD;
• 60 for all standard roads outside the CBD;
• 120 for the expressway.

These speeds are measured in kilometers per hour.

Picture of the grid

Everything inside, and including, the bold black outline, is the Central Business District. The blue outline represents the expressway.

Challenge

Write a GPS which takes in a start intersection and end intersection, and attempts to output the fastest route from the start to the end. The "intersection" must be an intersection between two roads and can be specified in whichever reasonable input format you would like. You could take the row and column, the names of the two roads, etc. as long as it's reasonable.

Your output should be a list of directions in whichever reasonable output format you would like. Each direction should specify the direction to turn (straight, left, right, and for the expressway, enter/exit), the road to turn on and the number of "kilometers after the previous direction" to wait before executing this direction. For instance, "After 7km, exit the expressway onto 12E (East)". If the direction is to be executed while on the expressway, it must not take intersections into account. Your program may optionally decide to omit directions telling the user to "continue straight", but it may not omit any other direction. As shown above, directions telling the user to enter or exit an expressway must specify the direction to head upon entry ("enter the expressway (South)", for instance). You may direct the user in any direction from the starting intersection, and arrive at the end intersection from any side. It should also tell the user for how long he or she will have to drive, down to the second, and, optionally, the distance he or she will have to drive, which is necessarily measured in kilometers.

Your GPS may assume that the user will always be driving at the speed limit. It may also assume that the start and end are different.

Scoring

There are 225 x 224 = 50400 ways to choose start/end pairs. Your GPS will be scored based on the sum of the amounts of time it takes to drive from the start to the end, for each pair of start/end points. The GPS with the smallest total is the winner.

In the unlikely event of a tie between two or more submissions, length of code shall be the tiebreaker.

No test cases because there is never a single route for any start/end pair.

---

The tags for this challenge are code-challenge, path-finding, and grid.

Answer 8

Play chess (KOTH)

Your task is to write a chess engine that will compete with other submissions in a chess tournament. Well, almost. Since writing a full engine can be a bit tedious, you only need to write the evaluation function.

An evaluation function takes a chessboard as input and returns how "favorable" the position is. If white is winning, the evaluation function should return a large positive number. If black is winning, a large negative number. If the situation is tied, a number close to zero.

Chess engines then simulate different possible games to some depth and choose the moves that lead to the best result.

A classic evaluation function is as follows:

• Set r=0
• For every white pawn, add 1. For every black pawn, subtract 1.
• Same for knights and bishops, except add or subtract 3.
• For rooks, use 5
• And for queens, use 9

This evaluation function only takes into account material advantage; that is, just the raw amount of different pieces. More complicated evaluation functions may consider the position of individual pieces, what kind of structures do the pawns form etc.

Your task is to write an evaluation function in C in at most 150 bytes. The evaluation function takes as input 7 bitboards. A bitboard is a 64-bit integer that assigns one bit to every square of the chessboard. The first bitboard has a bit set for every piece in the chessboard. The second one encodes the owner of the piece. The remaining bitboards have a bit set for every pawn, knight, bishop, rook and queen respectively. There is no bitboard for the king, since you can calculate it using the first and last 5 bitboards. Your function will return a signed integer.

For your convenience, I've aliased __builtin__popcount to p and uint64_t to q, and also included every standard header. You should name your function e.

Note that a slow evaluation function means that the engine won't be able to search as deep as with a fast one.

TODO: more details... and also write the engine

Meta

• Is 150 bytes a good number?
• Almost tempted to not alias the popcount... would have interesting results

Answer 9

Count the ways to transform (2)

Your input is a matrix (2d array) of positive integers. For example:

\begin{matrix} 1 & 1 & 4 & 7\\ 1 & 3 & 5 & 6\\ 2 & 1 & 4 & 5 \\ \end{matrix}

A semi-continuous transformation of this matrix is a rearranging of elements that preserves immediate neighbors. For example, we can swap the \$2\$ in the bottom left, and the \$1\$ in the top left corner.

\begin{matrix} 2 & 1 & 4 & 7\\ 1 & 3 & 5 & 6\\ 1 & 1 & 4 & 5 \\ \end{matrix}

This is fine, because every number has the same neighborhood counts. That is, we can make a sorted list of numbers and their neighbors, and verify the they are the same:

\begin{matrix} \text{Number} & \text{Neighbors} \\ 1 & 1,1 \\ 1 & 1,2,3 \\ 1 & 1,3,4 \\ 1 & 2,3,4 \\ 2 & 1,1 \\ 3 & 1,1,1,5 \\ 4 & 1,5,7 \\ 4 & 1,5,5 \\ 5 & 3,4,4,6 \\ 6 & 5,5,7 \\ 7 & 4,6 \end{matrix}

Here is another example.

\begin{matrix} 2 & 1 & 1\\ 1 & 3 & 1\\ 1 & 1 & 4\\ \end{matrix}

Let's make a neighbor list. Note that we are gonna have duplicate entries (which is fine)

\begin{matrix} \text{Number} & \text{Neighbors} \\ 1 & 1,1 \\ 1 & 1,1 \\ 1 & 1,2,3 \\ 1 & 1,2,3 \\ 1 & 1,3,4 \\ 1 & 1,3,4 \\ 2 & 1,1 \\ 3 & 1,1,1,1 \\ 4 & 1,1 \\ \end{matrix}

Now, can we swap the top left \$2\$ and the bottom left \$1\$? It may look fine at first glance, but we must be careful! By swapping those two elements we would create a \$1\$ which has neighbors \$2,3,4\$, which didn't exist in the first input.

Just to demonstrate, here is the matrix after this non-semi-continuous transformation:

\begin{matrix} 1 & 1 & 1\\ 1 & 3 & 1\\ 2 & 1 & 4\\ \end{matrix}

And here is the neighbor list:

\begin{matrix} \text{Number} & \text{Neighbors} \\ 1 & 1,1 \\ 1 & 1,1 \\ 1 & 1,1,3 \\ 1 & 1,2,3 \\ 1 & 1,3,4 \\ 1 & 2,3,4 \\ 2 & 1,1 \\ 3 & 1,1,1,1 \\ 4 & 1,1 \\ \end{matrix}

Which is has changed after the transformation, ergo the transformation is non-semi-continuous (on this input).

To clarify, semi-continuity is a property of a transformation on some specific matrix.

Your code will take a matrix as input and output the number of (unique) semi-continuous transformations. Two transformations are different if the output is different. So for example swapping two identical numbers is the same as the identity transform (doing nothing).

Or in other words: Your code will take a matrix and return the number of matrices with those dimensions that have the same neighbor-list.

Answer 10

Trap the persistent hero in a maze

Last time a challenger tried to thwart your evil magical deeds, they got trapped in a maze that you created to be as small as possible, giving up only a few steps from the exit. Now there is another hero on the way. If it ain't broke, why fix it, so you ask the magic ball about the moves the hero will make in the maze. There are good news, and bad news.

The good news is that the hero's moves are still predictable. There is a list of moves, which determine how the hero moves in an intersection. The bad news is that the hero is persistent, never really giving up. What this means is that the list of moves repeats forever.

TODO Explanation of the move list and rules

Your task is to write a program that traps the hero in the maze. You may assume that the input has a solution.

Answer 11

Count count count.. code-golf

Posted

Answer 12

Alphabet Polygon

Intro

Given a number of sides \$a\$ and a side length \$b\$, generate an \$a\$-sided polygon with side length \$b\$. The fill value will be the alphabet going clockwise. If there are not enough letters, wrap around.

Test cases

3 4

     A
    H B
   I   C
  G F E D


4 4

ABCD
L  E
K  F
JIHG
```

Answer 13

Shuffle up a list

Given two lists \$A\$ and \$B\$, with no repeats in elements and so that the elements of \$B\$ are identical to the elements of \$A\$ except for the order they are in, we say \$B\$ is an \$n\$-well-shuffled list of \$A\$ (where \$n\$ is a nonnegative integer) if:

• For any \$(a_1, a_2, \cdots, a_n) \in A^n\$, \$a_1\$'s position in \$A\$ is \$\neq\$ its position in \$B\$, \$a_2\$'s position in \$A\$ is \$\neq\$ its position in \$B\$, ... and \$a_n\$'s position in \$A\$ is \$\neq\$ its position in \$B\$
• For any \$(a_1, a_2, \cdots, a_n) \in A^n\$, if \$a_i\$ precedes \$a_j\$ for some \$(i, j) \in [1, n]^2\$ in \$A\$, then \$a_i\$ follows \$a_j\$ in \$B\$

Your task is to take two nonnegative integers \$m, n\$ as input and return how-many \$n\$-well-shuffled lists of lists of length \$m\$ there are.

Answer 14

Is this a Hamiltonian cycle?

Answer 15

Climbing the Bookshelf code-golf

Climbing the Bookshelf

Answer 16

Is it an action?

abstract-algebra decision-problem code-golf

---

Today, you will solve an abstract algebra challenge.

Consider a set \$G\$, which, to simplify things, is a finite subset of \$\mathbb{Z}\$ containing \$0\$. It has a binary operation \$*\$, which for our example will be \$+\$, but your program should be able to handle any binary operation. If \$G\$ is closed under \$*\$, i.e. \$g * g' \in G \forall g, g' \in G\$, there is associativity with regard to \$*\$, there is a unique element in \$G\$, which we will note as \$1_G\$, such that \$1_G * g = g * 1_G = g \forall g \in G\$, and there exists a unique \$g^{-1} \in G \forall g \in G\$ such that \$ g * g^{-1} = g^{-1} * g = 1_G \$, then \$G\$ is a group.

Consider a set \$X\$, which is also a finite subset of \$\mathbb{Z}\$. Then \$\circ: G \times X \to X\$, where \$G\$ is a group, is an action if:

• \$1_G \circ x = x \forall x \in X\$, and
• \$g \circ (g' \circ x) = (g * g') \circ x \forall g, g' \in G, x \in X\$ (associativity).

Challenge

Your task is to write a program or function which takes in the following:

• \$G\$, a finite subset of \$\mathbb{Z}\$ that includes \$0\$;
• \$X\$, also a finite subset of \$\mathbb{Z}\$, but not necessarily the same as \$G\$;
• a binary operation \$*\$ that operates within \$G\$ and that makes \$(G, *)\$ a group, which can be taken in any reasonable manner you would like, such as taking it as a function with two parameters, and
• an "application" \$\circ\$ from \$G \times X\$ to \$X\$, which can be taken in any reasonable manner you would like.

For the purposes of this challenge, \$1_G\$ is always \$0\$.

This program should then output true if \$\circ\$ is an action and false if not. You may use any two distinct values for true and false.

The shortest code, measured in bytes, wins.

Test cases.

\$G = \{0, 1, 2\}\$

\$X = \{1, 2, 3\}\$

\$*\$ defined by \$g * g' = (g + g') mod 3\$

\$\circ\$ defined by \$g \circ x = g + x\$

Output: false because:

• \$1_G\$ is 0;
• then \$1_G \circ x = 0 \circ x = 0 + x = x\$;
• but \$(1 * 2) \circ 2 = 0 \circ 2 = 2 \neq 1 + (2 + 2) mod 3 = 1 + (2 \circ 2) = 1 \circ (2 \circ 2)\$, thus \$\circ\$ is not associative.

\$G = \{0, 1, 2\}\$

\$X = \{0, 1, 2\}\$

\$*\$ defined by \$g * g' = (g + g') mod 3\$

\$\circ\$ defined by \$g \circ x = (g + x) mod 3\$

Output: true because:

• \$1_G\$ is 0;
• then \$1_G \circ x = 0 \circ x = (0 + x) mod 3 = x mod 3 = x\$ (because \$x < 3\$);
• and \$\circ\$ is associative (proof not provided)

Answer 17

Quicksand

In this fastest-code challenge, you take a positive integer as input, which represents the height of a sand pile, located at (0,0) on an infinite square grid. For example, if our input is 123, the sand grid looks initially like this:

\$\begin{matrix} 0 & 0 & 0 \\ 0 &123& 0 \\ 0 & 0 & 0 \end{matrix}\$

Now, piles of sand are unstable, so they topple if their height is 4 or greater. When sand piles topple, they send sand equally in all four directions, but due to the quantum nature of sand, the amount sent is an integer. Or in other words, if there is a pile of height n, it sends sand as follows:

\$\begin{matrix} 0 & \lfloor\frac{n}{4}\rfloor & 0 \\ \lfloor\frac{n}{4}\rfloor & n\mod 4 & \lfloor\frac{n}{4}\rfloor \\ 0 & \lfloor\frac{n}{4}\rfloor & 0 \end{matrix}\$

This means that sandpiles evolve step by step. For example, if we have this initial position, here's how the sandpiles evolve.

\$\begin{matrix} 0 & 0 & 0 & 0 \\ 0 & 0 & 6 & 0 \\ 0 & 2 & 7 & 0 \\ 0 & 0 & 0 & 0 \end{matrix}\$

\$\begin{matrix} 0 & 0 & 1 & 0 \\ 0 & 1 & 3 & 1 \\ 0 & 3 & 4 & 1 \\ 0 & 0 & 1 & 0 \end{matrix}\$

\$\begin{matrix} 0 & 0 & 1 & 0 \\ 0 & 1 & 4 & 1 \\ 0 & 4 & 0 & 2 \\ 0 & 0 & 2 & 0 \end{matrix}\$

\$\begin{matrix} 0 & 0 & 2 & 0 \\ 0 & 3 & 0 & 2 \\ 1 & 0 & 2 & 2 \\ 0 & 1 & 2 & 0 \end{matrix}\$

Now, since all the sandpiles have less than 4 sand, this sand grid is stable.

Rules

Your task is to take an positive integer \$i\$ as input, and output the eventually stable grid that the following initial position evolves to:

Todo add cool fractals

\$\begin{matrix} 0 & 0 & 0 \\ 0 & i & 0 \\ 0 & 0 & 0 \end{matrix}\$

(Note that the grid is still infinitely big)

The output format should be the following: "width;data", where width is an odd number representing the width a square that bounds the eventually stable arrangement (width doesn't have to be the smallest possible). Next is the raw data, which is just the square section of the grid flattened, and the numbers are represented with digits "0123"

Answer 18

Word Guess KOTH

Inspired by Wordle and Evil Wordle.

A King of the Hill game where you must write a bot which acts as both Guesser and Judge of a word guessing game. Each bot will play a match against all the other bots. Each match will consist of 10 rounds alternating between judge and guesser. A bot's score for the match is the number of guesses the opponent made minus the number of guesses it made. Higher is better. Bot with the highest average [or total?] score is KOTH.

The game is as follows:

1. The Judge and Guesser are both provided with the same dictionary of N letter words.
2. The Judge selects an answer from the dictionary.
3. The Guesser makes a guess. The candidate word must be contained in the dictionary.
4. The Judge is given the guess, and provides a score according to the following rules.

• The score is a string of N characters from the set ['G','O','B'], corresponding to the guessed letters

  • A 'G' indicates that the guessed letter is correct for that position. Great
  • A 'O' signifies that the guessed letter is in that answer but not that position. Out-of-place.
  • A 'B' indicates that the guessed letter is not in the answer. Bad.

• If a letter appears in the guess more than once, there will never be more non-'B' results than instances of that letter in the answer.

  • for example if the answer is 'ruler' and the guess is 'belle', the score will be 'BOGBB'.

4. Steps 2 and 3 continue until the score is all 'G's.
5. The the number of guesses is added to the Judge's score and subtracted from the Guesser's.

• Note that the judge is free to modify the answer after each guess, as long as the new answer is consistent with all the previous guesses.

An example scoring function in Python is:

def count_score(truth, trial):
    score = [None]*len(truth)
    allow = truth
    for index,value in enumerate(trial):
        if truth[index]==value:
            score[index]='G'
            allow=allow.replace(value,'',1)
        for index,value in enumerate(trial):
        if not score[index]:
            if value in allow:
                score[index]='O'
                allow=allow.replace(value,'',1)
            else:
                score[index]='B'
    return ''.join(score)

Entries must provide a bot command that can be called from the command line and prints the required outputs to stdout, separated by newlines.

For all the use cases below, codex is a filepath to a dictionary of legal words, and token is a string used by a bot to maintain state. It must not be empty. The token generated in any round is passed back to the same bot in the following round. The opponent bot will never see your token. Tokens are not retained from one round to the next.

arguments --> results

codex "judge" --> token Judge initialization. Returns a token.

codex "judge" token trial --> token score Judge will score the trial word. score is constructed according to the rules above.

codex "guess" --> token trial Guesser makes initial trial guess.

codex "guess" token score - token trial Guesser gets score from previous guess. Returns new trial guess.

Example Bot:

import random,sys,re

def begin_offer(codex):
    words = [l.strip() for l in open(codex)]
    return [random.choice(words)]

def score_trial(token, trial):
    return token, count_score(token,trial)

def first_guess(codex):
    words = sorted([l.strip() for l in open(codex)])
    guess = words[0]
    return (guess, guess)

def later_guess(codex, prior, score):
    words = sorted([l.strip() for l in open(codex)])
    index = words.index(prior)
                  
    for place,value in enumerate(score):
        if value != 'G':
            while words[index][place]==prior[place]:
                index+=1
            break
    guess = words[index]
    return guess,guess


if __name__ == "__main__":
    codex,style,*extra = sys.argv[1:]
    if style == 'judge':
        if not extra:
            result = begin_offer(codex)
        else:
            result = score_trial(*extra)
    elif style == 'guess':
        if not extra:
            result = first_guess(codex)
        else:
            result = later_guess(codex,*extra)

    print("\n".join(result))

Match Runner (in progress)

import sys,subprocess
def reply_split(reply):
    return [bites.decode('ascii').strip() for bites in reply.split()]

if __name__ == "__main__":
    judge,guess = sys.argv[1:]

    reply = subprocess.check_output([judge, "words.txt", "judge"])
    judge_token,*trash = reply_split(reply)

    reply = subprocess.check_output([guess, "words.txt", "guess"])
    guess_token,trial = reply_split(reply)

    for round in range(10):

        print(trial)
    
        reply = subprocess.check_output([judge, "words.txt", "judge", judge_token, trial])
        judge_token,score,*trash = reply_split(reply)

        print(score, "\n")
        if score == 'GGGGG':
            print("{} guessed {}'s word in {} rounds".format(guess, judge, round+1))
            break
        
        reply = subprocess.check_output([guess, "words.txt", "guess", guess_token, score])
        guess_token,trial,*trash = reply_split(reply)

    print(round+1)

Answer 19

Bracket Depth List

Answer 20

Decompress a ragged list

Answer 21

Very simple auto battler

There are two players. Each player has a team of between 0 and 5 members. Each member has two relevant statistics: an attack score and a health score. These range from 1 to 50.

Until at least one team runs out of members, you need to battle the lead member of each team against each other. (You can decide whether this is the first or last member of the team.) The two attacks are simultaneous, so it's possible that both members can defeat each other. Each attack reduces the foe's health by the user's attack. Once a team member's health is reduced to zero (or less) then it faints and takes no part in the rest of the battle.

If both teams simultaneously run out of unfainted members then the result is a draw otherwise the team that still has unfainted members wins.

Your task, given two teams in a reasonable format, e.g. list of tuples of (health, attack), is to write a program or function that outputs which (if any) team will win, using one of three specific values of your choice, e.g. -1, 0 and 1, or A, B and D. (Please describe the mapping of values in your answer.)

This is code-golf, so the shortest program or function that breaks no standard loopholes wins!

Sample team generator and battler

Answer 22

Triangle Tripler

Answer 23

Interpret Subleq code

code-golf parsing

Background

Subleq is a language that has only one 3 argument instruction. The instruction has three operands A B C. When executed it subtracts the contents in address A from address B; stores the result in address B; if the result is less than or equal to 0 it goes to address C. -1 in a position has special meaning. -1 in A will read the ASCII value of then next character of input into B; if no more input then goto 'C'. -1 in B will send the ASCII character in A to output. -1 in C will exit the program instead of going to an address.

Task

Given input and Subleq code, output the results from running the Subleq code.

An interpreter built in Excel is here.

Rules

• You may use any standard I/O method
• Standard loopholes are forbidden
• This is code-golf, so the shortest code in bytes wins

Test Cases

For the test cases below, any input to the Subleq is before the '/', code is after. Code is represented by decimal numbers.

Hello, World!

Input=>
/
12 -1 13
1 0 6
3 2 -1
4 4 0
72 101 108 108 111 42 32 87 111 114 108 100 33
Output
Hello, World!

!I!n!s!e!r!t! !i!n!b!e!t!w!e!e!n!

Input->
1 2 3 4 5 6/
2 -1 33
-1 8 -1
8 -1 0
8 8 
Output
!1! !2! !3! !4! !5! !6!

Meta

• What am I leaving out?
• Is there a better way of handling the input to the Subleq code?
• Does it need more/better examples?

Answer 24

Generate all groupings

Answer 25

Bigger regex?

Answer 26

Knights Jam | Chess

Answer 27

Factorials of primes decomposition

Answer 28

Play 1D minesweeper

Answer 29

Page Selector

Answer 30

Can the Tune be Played?

I changed the question slightly from when it was posted on the Sandbox.