Questions tagged [code-golf]
Code-golf is a competition to solve a particular problem in the fewest bytes of source code.
9,790
questions
13
votes
14answers
285 views
Sum the array times n, except the last
I've been posting relatively hard challenges recently, so here goes an easy one.
Task
Given an array \$A\$ and a number \$n\$, calculate the sum of all numbers of \$A\$ multiplied by \$n\$, except the ...
10
votes
10answers
399 views
Solve a 2xN Maze
Given a \$2\times N\$ maze, determine if you can get from the start top left corner to end bottom right corner using only up, down, left, and right moves.
Input
A \$2\times N\$ block (\$1 <= N <=...
8
votes
7answers
2k views
Music with pi and e
Because I forgot to celebrate the pi-day(14.3) lets celebrate with \$\pi\$, \$e\$ (Euler's number) and music!
Challenge
No, we don't have time to eat a pi-pizza, lets make a program.
What you need is ...
8
votes
2answers
216 views
Distributive on myself
Background
We all know about distributivity, i.e. \$a(b+c) = ab + ac\$. This is a property on 2 different operations, namely addition and multiplication. But indeed, nothing can stop us from studying ...
7
votes
11answers
697 views
Counting King's Hamiltonian Paths through 3-by-N grid
Background
A Hamiltonian path is a path on a graph that steps through its vertices exactly once. On a grid, this means stepping through every cell exactly once.
On a square grid, a Chess King can move ...
20
votes
14answers
2k views
A long long time ago, in a galaxy … right here
Task
Given a positive integer return the geologic era and period it was that many million years ago.
Input/output
The input is a string or integer; the output is a string. Eras and periods are ...
18
votes
28answers
2k views
Find the perfect square!
Your task is to turn a square root like this:
√12
into a form like this:
2√3
For our purpose, we only need to output the left ...
14
votes
17answers
2k views
Are they collinear?
Task
Write a program/function that when given three 2d points in cartesian coordinates as input outputs a truthy value if they are collinear otherwise a falsey value
Three points are said to be ...
13
votes
3answers
1k views
Implement a UNIX file system and command line parser
Description
Your task is to implement a simple UNIX command parser and file system. Your program will have to implement a file system that can be modified via commands.
The starting directory of your ...
14
votes
6answers
714 views
Implement 1-dimensional version of Multi-Take
Background
Adám and I were once discussing a way to properly extend some features in Dyalog APL. I came up with the following extension to Take, a function that takes some front or back elements (and ...
11
votes
5answers
402 views
Verify Tents and Trees solution
Background
Tents and Trees (try here) is a puzzle played on a square (or rectangular) grid, where the objective is to place tents horizontally or vertically adjacent to each of the trees, so that no ...
8
votes
9answers
1k views
Lumberjaxe Code Golf
Tom the lumberjack is going to do his daily routine: chop trees. After all, it's his job to do so. His boss has ordered him to chop trees in a straight line marked with a special tape to identify them,...
7
votes
8answers
213 views
Is it a geometric sequence or not? [closed]
Well, last time I asked for an arithmetic sequence, now comes the geometric sequence
Challenge
In this challenge, the input will be an unordered set of numbers and the program should be able to tell ...
4
votes
2answers
976 views
Shortest python3 code for: Find the difference between a number and a power of two not exceeding a given number
So, this is a task from one very popular educational site in Russia:
https://acmp.ru/index.asp?main=task&id_task=786&ins=1
Mathematically, you need to find the power of two not exceeding the ...
14
votes
4answers
735 views
Eight days a week
Back in 1965, The Beatles released their hit song 'Eight Days a Week'.
In this code-golf challenge we are going to reimagine dates of the 21st century as if there really were eight days a week.
Input
...
21
votes
2answers
1k views
Get string “-” with JavaScript using only the symbols from “+[]”
Challenge: Get the JavaScript string value containing only the "-" character using code only containing the following three symbols: ...
-6
votes
4answers
174 views
Is it an Arithmetic Sequence or not? [closed]
Challenge
In this challenge, the input will be an ordered set of numbers and the program should be able to tell if the set of numbers is an Arithmetic Sequence.
Input
The input will be a list ...
17
votes
16answers
2k views
Find the discrete logarithm
Task
Write a program/function that when given 3 positive integers \$a, b\$ and \$m\$ as input outputs a positive integer \$x\$ such that \$a^x\equiv b\ (\text{mod}\ m)\$ or that no such \$x\$ exists.
...
24
votes
20answers
1k views
Logo Pack LAPACK
This is the logo for LAPACK, a widely used software library for numerical linear algebra.
Your task is to print the logo (color and matrix brackets not required) as this exact string. Trailing ...
14
votes
9answers
1k views
How many numbers can we make?
You are given a non-empty list of positive integers. Your task is to figure out how many distinct numbers can be obtained by applying the following algorithm:
Remove either the first or the last item ...
4
votes
5answers
205 views
Divide into 2 isosceles triangles
Given the measures of two of the interior angles of a triangle (x and y; the other angle can be easily calculated with ...
27
votes
23answers
3k views
14
votes
3answers
250 views
Identify the smallest possible tile in the matrix
Challenge
Given a matrix of digits (0-9), find the smallest (in terms of area) rectangular matrix of digits where one or more copies of itself, possibly rotated, can tile the original matrix. ...
31
votes
9answers
5k views
Is there a face in this image?
Help, I've been diagnosed with prosopagnosia! This means I'm no longer able to recognise faces.... :(
Can you help me?
The challenge
You will be given an image as a matrix of regular ASCII characters ...
23
votes
4answers
3k views
Orientation Oriented Programming
Write a program for a specific language that in different orientations performs different tasks.
Your code should have at least two non-empty lines and at least two non-empty columns and should ...
-2
votes
1answer
161 views
Format yourself for codegolf! [duplicate]
Task
Your task is to write a program that, taking no input, outputs a string that represents a formatted codegolf answer of itself. The pattern is the following:
...
10
votes
21answers
2k views
How many weekdays?
This a simple question.
The start day is a Saturday and let the input be a non-negative number x.
The output should be the number of weekdays (Mon-Fri) in the next <...
13
votes
8answers
1k views
Is a statement of propositional logic always true?
The challenge is to golf a program that checks if a statement of propositional calculus/logic is a logical tautology (i.e. it is true for all possible values of the variables).
Input
Input formulas ...
2
votes
2answers
160 views
Create a text image by manual automation
Challenge
Premise
It's 2006, and Alice is trying to send Bob their her completed notes on their newly ended expeditions into the labyrinthine school library, which the two of them found suffers from a ...
10
votes
8answers
714 views
Scientific notation in Base-16
Input a scientific notation number (base 10), output scientific notation in base 16 (as defined below).
Details
In scientific notation, all non-zero numbers are written in the form
$$ m \times 10^n $$
...
21
votes
6answers
2k views
The matrix has U
Given a matrix of size at least 3×3 formed by positive integers, determine if it contains at least one "U" pattern, defined as
...
10
votes
2answers
271 views
The one counting challenge to rule them all!
Background
Mathematicians are interested in all kinds of algebraic structures, e.g. groups, rings, boolean algebras. Generally, we have several operations (addition, multiplication, meet, join, etc.), ...
13
votes
4answers
2k views
Archimedes's cattle problem
Compute, O friend, the number of the cattle of the sun which once grazed upon the plains of Sicily, divided according to color into four herds, one milk-white, one black, one dappled and one yellow. ...
6
votes
3answers
348 views
Is this stack of CNN layers valid?
Background
This challenge is about Convolutional neural networks, and its two main building blocks, namely Convolutional layer and Pooling layer.
For simplicity, we ignore the "depth" of the ...
22
votes
3answers
995 views
Baba is golf, flag is win
If you haven't played the game Baba is You, I think you really should. Whether you’ve played it or not, have a go at implementing it as a code golf.
The idea behind this challenge is to have a bit ...
-1
votes
6answers
437 views
LeetCode 552: Student Attendance Record II
I'm posting my code for a LeetCode problem copied here. If you have time and would like to golf for a short solution, please do so.
Requirement
It has to only pass the LeetCode's Online Judge, if the ...
17
votes
2answers
1k views
Is this a valid Shakashaka solution?
Background
Shakashaka is a puzzle on a grid, whose objective is to place some half-squares (right triangles) on the empty cells so that all the remaining contiguous regions form rectangles, either ...
29
votes
11answers
2k views
Implement Entombed's lookup table
Background
Entombed is an Atari 2600 game released in 1982, with the goal of navigating through a continuous mirrored maze as it scrolls upwards. In recent times, the game has been subject to research ...
0
votes
0answers
97 views
I am surely the fastest!… asymptotically [duplicate]
Background
You are probably familiar with the "asymptotic time complexity" concept, which provides a way to measure how fast an algorithm runs as the input gets larger. For instance, if an ...
11
votes
1answer
295 views
Scoring Quantum Tic-Tac-Toe
In the description of this challenge, the following board will be used as a reference for positions:
ABC
DEF
GHI
For instance, in a game of ordinary tic-tac-toe, <...
22
votes
9answers
967 views
Split pythagorean triples into two sets
Task
Write a program/function that when given a positive integer \$n\$ splits the numbers from \$1\$ to \$n\$ into two sets, so that no integers \$a, b, c\$, satisfying \$a^2 + b^2 = c^2\$ are all in ...
12
votes
3answers
252 views
Friendly Incenters
The incenter of a triangle is the intersection of the triangle's angle bisectors. This is somewhat complicated, but the coordinate formula for incenter is pretty simple (reference). The specifics of ...
16
votes
25answers
2k views
Turn a sentence into a dictionary
For this challenge, you will be given a long string as an input. With this string, you must create a dictionary.
Details:
This dictionary will contain all the words from the string - a word being any ...
7
votes
4answers
454 views
Find the date that is n days from January 1st 1984
This challenge is a relatively simple concept that I'm surprised has not been done yet. You will be given only an integer as an input. Your task is to find the date that is this number of days from ...
13
votes
3answers
528 views
Can this polyomino tile the toroidal grid?
Inspired by certain puzzles on Flow Free: Warps.
Background
We all know that L-triominos can't tile the 3x3 board, and P-pentominos can't tile the 5x5 board. But the situation changes if we allow the ...
20
votes
14answers
2k views
Get to the Zone!
You are playing a famous game called \$1\text{D Array BattleGround}\$. In the game, the player can be stationed in any position from \$0\$ to \$10^5\$.
You are a Paratrooper in the game and have the ...
5
votes
0answers
208 views
Find the busiest hour for each stackexchange site [closed]
Input
Name of a stackexchange site or any way to uniquely identify the site.
Output The hour of the day that had the largest number of answers posted over the previous 24 hours. E.g. 14:00-15:00 GMT.
...
16
votes
6answers
622 views
Represent n as an expression containing all the digits
Related Challenge: Single Digit Representations of Natural Numbers
Task
Write a program/function that when given a non-negative integer \$n \le 100000\$ outputs an expression which uses all the ...
17
votes
2answers
396 views
What is the fastest safe way down a mountain?
Intro
Help! I'm stuck on a snow-covered mountain and I need to get down as fast as possible, preferably without dying. I have a map showing how high each part of the mountain is above the normal ...
17
votes
24answers
3k views
What calculator is this datafile for?
The challenge today is very simple. The task is to determine the TI calculator for which the submitted datafile was made.
The datafiles always start with a string ...
