Questions tagged [code-golf]
Code-golf is a competition to solve a particular problem in the fewest bytes of source code.
11,089
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Calculate the Lowest Even-Harmonic of the Values in a List
PROBLEM
For a list of numbers, list: Find the lowest possible integer, x, which is optimally close to the whole number even-...
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vote
0
answers
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Figure out the least amount of duplicate data to fill a quota [closed]
You are given 100 arrays/sets of 5-8 numbers between 1-20. If you combine all the arrays you will always get at least one of each number (1-20), so don't worry about an "unsolvable" case. ...
16
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11
answers
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Straighten my corners... diagonally
We can arrange the positive integers like this:
1_| 2 | 5 | 10
4___3_| 6 | 11
9___8___7_| 12
16 15 14 13
That is, in L-shaped brackets expanding down and right ...
29
votes
31
answers
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Previous Fibonacci number
The sequence of Fibonacci numbers is defined as follows:
\$
F_0 = 0 \\
F_1 = 1 \\
F_n = F_{n-1} + F_{n-2}
\$
Given a Fibonacci number, return the previous Fibonacci number in the sequence. You do not ...
15
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25
answers
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Reverse hex cipher
Characters in strings are sometimes represented as their ASCII hexadecimal codes. Printable characters have two hex digits in their representation. Swapping those digits leads to another character, ...
32
votes
32
answers
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Eh, codegolf shmodegolf
This challenge is about implementing Shm-reduplication, originating in Yiddish, where one takes a word, duplicates it, and replaces the first syllable in the second word with "Shm" in order ...
15
votes
16
answers
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Divisible subset sums
Inspired by the recent 3Blue1Brown video
Consider, for some positive integer \$n\$, the set \$\{1, 2, ..., n\}\$ and its subsets. For example, for \$n = 3\$, we have
$$\emptyset, \{1\}, \{2\}, \{3\}, \...
12
votes
8
answers
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Can a run ascending list be made?
A run ascending list is a list such that runs of consecutive equal elements are strictly increasing in length. For example [1,1,2,2,1,1,1] can be split into three ...
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Generate All 8 Knight's Moves
Introduction
In chess, Knights can move two squares in one direction, and then one square in an orthogonal direction. On an x/y plane, these can be thought of as being a relative change of coordinates,...
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12
answers
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I want 8 bits for every character!
This is the reverse of this challenge.
Given an encoded list of codepoints and the characters used to encode it, you need to decompress it to its original string.
For example, given the encoded list <...
18
votes
12
answers
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In between fractions
Given two positive integer fractions \$x\$ and \$y\$ such that \$x < y\$, give the fraction \$z\$ with the smallest positive integer denominator such that it is between \$x\$ and \$y\$.
For example ...
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24
answers
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Find the nth Fibonacci number, where n is the mth Fibonacci number
Introduction
If fib(x) calculates the xth Fibonacci number, write a program that calculates ...
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votes
0
answers
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Find the Lowest Allowable Integer Which is an Optimal Even-Harmonic of the Values in a List [closed]
PROBLEM
For a list of numbers, list: Find the lowest possible integer, x, which is optimally close to the whole number even-...
14
votes
13
answers
703
views
Find the dimensions of a ragged list
For any ragged list its dimensions will be a list of non-negative integers defined as follows:
Elements that are not a list will have dimensions \$\textbf{[}\,\,\textbf{]}\$.
An empty list has ...
6
votes
2
answers
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Solve the Zany car game
The Zany Car Game is a tile matching game. You are given a number of tiles, with coloured cars split into a top and bottom half. To win the game, you need to find a square arrangement of the tiles so ...
12
votes
15
answers
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LOOOOONG TEEEEEXT
Definition of long text
Long text usually shows emphasis, for instance, loooooool or yaaaaaaaaaay. Usually the vowel is ...
16
votes
21
answers
2k
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Apartment Building
Draw an "apartment" building according to the specifications below.
Basic Rules
Take, as input, the number of floors of the building.
Return a building with that many floors meeting the ...
12
votes
8
answers
758
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Count the Liberties - Advanced
Here's an advanced version of the Count the Liberties challenge.
The definitions of the terms liberty and group are the same as the previous challenge, so have a look at the previous one for details, ...
16
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25
answers
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Alternating sums of multidimensional arrays
Given a multidimensional array, find the recursive alternating sum. An alternating sum is simply the sum of an array, where every other item (starting with the second) is negated. For example, the ...
13
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9
answers
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Magic: the Gathering - Colour Sorting
Related: Deck Names Friends or Foes Paying for Spells
The Magic: the Gathering card game has five colours of magical mana: white (W), blue (U), black (B), red (R), and green (G). Cards can be any of ...
14
votes
23
answers
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There's more than one way to skin a set
Given a set of positive integers \$ S \$, output the set of all positive integers \$ n \$ such that \$ n \$ can be made by summing a subset of \$ S \$ in more than one different way, i.e., that are ...
17
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Crossing a Lily Pond
The Narrative
You are a frog who is at the edge of a pond with waterlilies. You would like to cross the pond without getting wet, so you plan to jump from lily to lily. There is, however, one problem: ...
12
votes
9
answers
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Convert Alpha-2 to Alpha-3
The Task
The task is easy: given an Alpha-2 country code, output the Alpha-3 equivalent. The input may be in any case you choose, and the output in any consistent case of your choosing. Here are the ...
7
votes
2
answers
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Write a (simplified) BitCycle interpreter
Implement a function or program that can run simplified BitCycle code. The functions you must implement are:
<^>v: Change the direction of a bit to the ...
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13
answers
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Draw the Archimedean Spiral
Overview
I was playing with Desmos and discovered a really cool spiral:
Doing some research, I discovered that this spiral was the Archimedian spiral. Every point on the spiral is exactly \$\theta\$ ...
10
votes
15
answers
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center a matrix [closed]
The words "center a" probably give flashbacks to any decent HTML developer. Luckily, we are not working with divs, we are working with matrices.
Given a matrix where w=h, and given a "...
8
votes
6
answers
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Random Pixels Image Compression
Challenge:
Given an integer \$n\$, guaranteed to be \$\geq2\$ and a power of 2, we are going to draw multiply boards either side-by-side or below one another, where the first has dimensions of \$n\$ ...
20
votes
13
answers
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Bitwise XOR of floats
This is different from Floating Point XOR, and more in the spirit of a comment by R.. GitHub STOP HELPING ICE on that challenge, but I thought of this idea independently.
Generalized XOR
The bitwise ...
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votes
2
answers
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Is it a good chord?
Is it a good chord?
Definition of a chord:
We define a chord as three notes together.
Definition of a ...
4
votes
18
answers
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Palindromic Powers
Powers
We define an important power as a number that can be represented as \$ x^y \$ where \$ x ≥ 2 \$ and \$ y ≥ 2 \$.
Palindrome
We define an ...
27
votes
5
answers
3k
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Haplololololololology!
Haplology
Haplology is a linguistic term:
the omission of one occurrence of a sound or syllable that is repeated within a word, for example probly for probably.
For this challenge, it means ...
14
votes
10
answers
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Storing a band matrix
Related challenge
A band matrix is a matrix whose non-zero entries fall within a diagonal band, consisting of the main diagonal and zero or more diagonals on either side of it. (The main diagonal of a ...
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votes
6
answers
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Connecting Dots
Connecting Dots
We define a type of question on the test, connecting the dots
Question parameters
There are two parameters. Suppose they are 5 and ...
18
votes
6
answers
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Matrix Meets ASCII Art
A binary matrix represents a shape in the plane. 1 means a unit square at that position. 0 means nothing. The background is 0.
For example, the array ...
15
votes
7
answers
1k
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Euler characteristic of a binary matrix
A binary matrix represents a shape in the plane. 1 means a unit square at that position. 0 means nothing. The background is <...
20
votes
8
answers
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ASCII-Art n'th Root
Challenge:
Given two integers \$a\$ and \$b\$, with lengths \$A=length(a), B=length(b)\$, output an ASCII-art of the \$a^{th}\$ root of \$b\$, including the answer rounded to \$A\$ amount of decimal ...
5
votes
9
answers
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I Need Moore(less) Chips
If you wanted to compute a very large long problem, that on a machine that you could buy today for an inflation adjusted price, will take some amount of years/decades. The issue is, if you only have ...
9
votes
2
answers
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Sorting passengers on a plane
A few days ago I made a puzzle about moving people on an airplane. Now I am interested in the general version of this puzzle and the shortest code golf for it.
I will briefly summarise the puzzle here....
12
votes
5
answers
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Unshuffle my poker chips
This part is somewhat detached from the actual array manipulation side of the challenge, scroll down for an explanation that is much more array-based
You've been learning how to shuffle poker chips ...
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votes
28
answers
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Derivative of a product
In calculus, the derivative of a mathematical function defines the rate at which it changes. The derivative of a function f(x) can be marked as ...
21
votes
16
answers
4k
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Who needs 8 bits for one character?
Given a string and the characters used to encode it, you need to compress the string by only using as many bits as each character needs. You will return the character codes for each character needed ...
14
votes
6
answers
661
views
Rounding a range
You have a line with two endpoints a and b (0 ≤ a < b) on a 1D space. When ...
15
votes
25
answers
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Implement the Conjunction of a Three-Valued Logic
Your task, should you choose to accept it, is to take two input values \$a\$ and \$b\$,
where \$a\$ and \$b\$ are in the set \$\{T, U, F\}\$, and compute and output their logical conjunction in a ...
11
votes
7
answers
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views
Shortest restricted superstring
Given two sets of strings, \$ D \$ and \$ R \$, find the shortest string which contains every string in \$ D \$, but contains none of the strings in \$ R \$.
There are almost always multiple possible ...
12
votes
7
answers
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Is Wally there?
Inpired by recent Stand-up Maths' video.
Task
Wrapping a list x can be seen as inserting "line-breaks" into x every <...
3
votes
3
answers
197
views
Plot Slope Fields Given Differential Equation
Slope fields or direction fields, are a graphical representation of the solutions to a first-order differential equation of a scalar function. A slope field shows the slope of a differential equation ...
12
votes
11
answers
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Convert JSON object of directories to list of paths
Task
The input consists of a JSON object, where every value is an object (eventually empty), representing a directory structure. The output must be a list of the corresponding root-to-leaf paths.
...
19
votes
8
answers
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Convert Alpha-3 to Alpha-2
I've been developing some programs involving me fetching a vector from a url using Alpha-2 country codes (such as GET /jp.svg for Japan). Except, oh no! All the ...
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votes
17
answers
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Infinite Candle Sequence
I have a cake shop that specialises in birthday cakes. The cakes that I sell must have candles placed in a circle. You would probably think I can just divide 360° by the number of candles, but the ...
29
votes
28
answers
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Collatz Encoding
The Collatz Conjecture
The famous Collatz Conjecture (which we will assume to be true for the challenge) defines a sequence for each natural number, and hypothesizes that every such sequence will ...