Questions tagged [code-golf]
Code-golf is a competition to solve a particular problem in the fewest bytes of source code.
10,596
questions
5
votes
1answer
30 views
Best response to the Evolution of Trust?
Backstory
I was fiddling around with the Evolution of Trust and thought of this.Warning: I recommend you go check it out first before attempting this challenge.
Summary for people who haven’t played
A ...
15
votes
16answers
398 views
15
votes
3answers
571 views
Find the sliced sheet of paper
Context :
Suppose you have a sheet of paper measuring 8 x 10. You want to cut it exactly in half while maintaining its rectangular shape. You can do this in two ...
17
votes
14answers
1k views
Apply gravity to this matrix
This was inspired by this question.
Given an \$m\times n\$ matrix of \$0\$'s and \$1\$'s, apply "gravity" to it. This means to drop down all the \$1\$'s as if they were affected by gravity.
...
7
votes
2answers
274 views
Setting up Al's R session
Al wanted to use my computer to do some simple calculations, so I lent him the use of my R terminal for a bit. He complained though, saying it wasn't set up how he liked it. I said "No problem Al,...
8
votes
8answers
660 views
Neural Processing Lattice Checker
Consider the following 9 "row patterns", using 0s to represent empty cells and 1s to represent a full cell. Each pattern is associated with an integer \$n\$, such that \$0 \le n \le 8\$ (...
-1
votes
1answer
118 views
Find out your Ghost ghost name [duplicate]
Inspired by a tweet by Nathan W. Pyle
There is, now, a standard method of converting your boring, normal human name into a mysterious, ethereal Ghost Name™️. Ably described by Mr Pyle...
...
-1
votes
1answer
101 views
Convert American English to British English [duplicate]
One of the main differences between British and American English is that British English tends to say re instead of er in words like center and theater. Center becomes centre and theater becomes ...
1
vote
0answers
13 views
Has there been any large-scale attempt to assemble libraries or programs from aggressively-golfed solutions in a given language? [migrated]
It occurred to me when I was browsing threads here that there is an immense collection of simple and extremely space-efficient functions on this site.
Although I imagine the end result of such an ...
10
votes
6answers
2k views
Game of Life, but on a 4-8-8 tiling
Background
The 4-8-8 tiling looks like this:
For the purpose of this challenge, we take the orientation of the tiling as exactly shown above. In plain English words, we take the tiling so that it can ...
19
votes
19answers
2k views
Is it a row of Pascal's triangle?
Pascal's triangle is a triangular diagram where the values of two numbers added together produce the one below them.
This is the start of it:
...
4
votes
13answers
563 views
Written Word Equation
Word equations, but not as you know it! Given a sentence which will include two numbers, numerically, and a spelt operator, in the order seen in the examples, your goal is to give the numerical answer
...
5
votes
28answers
3k views
English An or A?
Given a string consisting of only upper and lower case letters, output an if it begins with a vowel, and a if not. For the ...
7
votes
4answers
211 views
So is that maximum?
Given a map from arrays of integers of same size to single integers, determine if there is a set of indices such that the output is equal to the maximum of the elements at those indices for every ...
13
votes
7answers
561 views
Convert to a non-adjacent form
Consider a form of binary where digits can be any of \$1\$, \$0\$ and \$-1\$. We'll still call this "binary" because we convert the digits from base two. For example,
$$\begin{align}
[1, 0, -...
14
votes
7answers
829 views
Simplify K projections
Background
K functions have a feature called projection, which is essentially partial application of values to a function. The syntax for projections is a natural extension of the regular function ...
10
votes
8answers
1k views
Implement a 2-tag system simulator
To quote http://brainfuck.org/utm.b:
A tag-system transforms strings over an alphabet A = {a[1], a[2], ... a[n], a[n+1]} as follows: a positive integer ...
7
votes
0answers
170 views
Jelly compression quine
The golfing language Jelly has a very complex and clever string compression system which I'm not going to go into depth about here. You can find a very good explanation here.
Basically, Jelly's string ...
3
votes
6answers
278 views
Yet another coin flipping problem
Problem
Starting with a set of 10 coins at the start where all coins are tails up, and given n number of integers \$x_1, x_2, x_3... x_n\$ representing n rounds of coin flipping.
At each round, we ...
32
votes
9answers
3k views
How many Jimmies does this platform need?
Platforms are stretches of - characters separated by one or more characters.
For example:
...
8
votes
13answers
3k views
Unlolify a lolified message
Unlolify a lolified message!
I had to ask a coworker if they wanted to have lunch with me, but we're both hackers so it could not be in a lame way. The message asking that was roughly this:
please ...
17
votes
10answers
1k views
Minimally prepend numbers to get a symmetric Young diagram
Background
A Young diagram is a diagram that represents a nonincreasing sequence of positive integers using left-justified rows of squares. As an example, 5, 4, 1 ...
20
votes
11answers
2k views
Greedy queens sequence
Challenge
Implement the "greedy queens" sequence (OEIS: A065188).
Details
Taken from the OEIS page.
This permutation [of natural numbers] is produced by a simple greedy algorithm: starting ...
4
votes
0answers
113 views
How many fill buckets to blank? [duplicate]
The fill bucket is a tool available in many drawing tools which replaces a contiguous chunk of one color with a another color.
We are going to define a fill bucket which operates on lists of non-...
16
votes
13answers
2k views
When's the Listening Party?
A listening party is an event where a bunch of people get together to listen to some music (like a viewing party, but for music). In the age of the internet you can do Listening Parties online with ...
14
votes
5answers
896 views
Non-sums of distinct positive powers
There are 31 positive integers that cannot be expressed as the sum of 1 or more distinct positive squares:
...
14
votes
3answers
505 views
Snap (card game)
When I was a child I used to play a variation of Snap to stake soccer trading cards.
"Game" is an overstatement because the only role of the players is to secretly prepare their starting ...
27
votes
27answers
2k views
Display a number in Toki Pona
Toki Pona is a constructed language with 137ish words, designed to constrain the speaker to expressing ideas in a simple and straightforward manner, reducing ideas to more essential forms.
Often, ...
16
votes
14answers
1k views
Euler's numerus idoneus
Euler's numerus idoneus, or idoneal numbers, are a finite set of numbers whose exact number is unknown, as it depends on whether or not the Generalized Riemann hypothesis holds or not. If it does, ...
10
votes
16answers
506 views
Generate all \$3\times 3\$ magic squares
Though challenges involving magic squares abound on this site, none I can find so far ask the golfer to print / output all normal magic squares of a certain size. To be clear, a normal magic square of ...
19
votes
29answers
2k views
Remove oddly nested substrings
Task:
Input will consist of some text, with nested [] separating some of it into nested groups:
...
11
votes
2answers
229 views
Draw constraint system #18762389
Background
Page 219 of A New Kind of Science (a book by Stephen Wolfram, the creator of Mathematica) shows an interesting 2D pattern generated by constraints. The relevant section in the book starts ...
6
votes
7answers
384 views
Distinct Subset Sums: Extending A276661
Consider the integer set \$S = \{3, 5, 6, 7\}\$. If we list all \$2^n\$ subsets of \$S\$ (its powerset) and calculate their sums, we get
$$
\mathcal{P}(S) = \{\emptyset, \{3\}, \{5\}, \{6\}, \{7\}, \{...
17
votes
10answers
994 views
How many iterations to reach the sequence?
Let's define a function \$f\$ which, given a positive integer \$x\$, returns the sum of:
\$x\$
the smallest digit in the decimal representation of \$x\$
the highest digit in the decimal ...
19
votes
27answers
2k views
Find me vowels near you
Write a function that takes in a string and for each character, returns the distance to the nearest vowel in the string. If the character is a vowel itself, return 0.
Vowels are : ...
13
votes
2answers
412 views
Draw me a shape
The game shapez.io has a lot of shapes. In my previous challenge, the object was to generate a random code for a shape. Now, your challenge is to render a shape.
Specs
Shapes
Each shape has a unique ...
-3
votes
3answers
465 views
Code golf edit distance up to 3 [duplicate]
The edit distance between two strings is the minimum number of single character insertions, deletions and substitutions needed to transform one string into the other.
This task is simply to write code ...
19
votes
18answers
2k views
Adaptive randomisation
Given a number \$n ≥ 2\$, a blackbox function \$f\$ that takes no arguments and returns a random integer in the range 0...n-1 inclusive, and a number \$m ≥ n\$, your challenge is to generate a random ...
19
votes
7answers
3k views
Hello, Toroidal Earth!
Your task is to create a program that outputs the string:
Hello, Toroidal Earth!
with an optional trailing newline.
Additionally if I remove the first line1 of ...
18
votes
16answers
2k views
Make me a shape
The game shapez.io has a huge variety of shapes you can produce, such as:
Each shape has a unique short code, for example the above is CrWbScRu.
This means, going ...
24
votes
31answers
3k views
"-rot" transform
Background
-rot transform (read as "minus-rot transform") is a sequence transformation I just invented. This transform is done by viewing the sequence as a stack in Forth or Factor (first ...
19
votes
19answers
2k views
Hunt for discount
Story
My local pizza delivery introduced new discount. You get 50% discount from every second item on your order.
But being greedy capitalists, they forgot to mention that they will rearrange items ...
21
votes
8answers
5k views
Make a Hello World using as many bytes as possible
Write a program that outputs the exact string:
jan ale o, toki!
("Hello, world" but in toki pona to prevent builtins.)
with an optional trailing newline.
...
27
votes
10answers
4k views
Distances between keys on a QWERTY keyboard
Inspired by this video by Matt Parker
The distances between the letter keys of a QWERTY keyboard are somewhat standardised. The keys are square and both the horizontal and vertical spacing are 19.05mm ...
9
votes
4answers
305 views
Parse Ternary Lambda Calculus for correctness
Wheat Wizard has once tried to come up with a parsing problem unsuitable for regex, but it failed due to Anders Kaseorg's Perl regex answer. This is the second attempt. Now that we know that Perl ...
15
votes
4answers
650 views
Could you massage this stack for me?
Forth is one of the few non-esoteric stack-based languages. For this challenge, we will use a small subset of Forth, which simply executes a sequence of words in a linear fashion — without any ...
25
votes
12answers
2k views
Rows of the Collatz tree
Consider a binary tree built the following way:
The root node is \$1\$
For a given node \$n\$:
If \$n\$ is odd, its only child is \$2n\$
If \$n\$ is even, one of its children is \$2n\$. If \$\frac {...
10
votes
8answers
903 views
Boustrophedon transform
Related: Boustrophedonise, Output the Euler Numbers (Maybe a new golfing opportunity?)
Background
Boustrophedon transform (OEIS Wiki) is a kind of transformation on integer sequences. Given a sequence ...
2
votes
0answers
123 views
Tips for Golfing the Lambda Calculus & Friends
This includes tips for all related derivatives, as coding in these langs often primarily consists of writing the function in the lambda calculus and then compiling it down at the end.
Among others, ...
29
votes
5answers
2k views
Stack the rocks
This is a rock:
*
Rocks can be stacked. Apart from the bottom-most layer, each rock must rest on two other rocks, like this:
...