A code challenge is a competition for creative ways to solve a programming puzzle with an objective winning criterion not covered by other scoring tags (e.g. code-golf).
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votes
2answers
215 views
Befunge Brain Teasers
Introduction
For the ones wondering what Befunge exactly is, it is a two-dimensional stack based language made in 1993 by Chris Pressy. I made 7 brain teasers that need to be solved in Befunge-93. ...
8
votes
3answers
309 views
Egg dropping contest
Your challenge:
You are on the 0th floor of a infinitely tall building. At any floor, you can walk to the window and drop an egg. Your goal is to figure out the highest floor that the egg can ...
110
votes
77answers
9k views
What is the smallest positive base 10 integer that can be printed by a program shorter (in characters) than itself?
I think the question as above is clear, but just in case:
Write a full program (not just a function) which prints a positive base 10 integer, optionally followed by a single newline.
Qualifying ...
6
votes
4answers
345 views
Staircase Program
The challenge is simple: given two parameters, x and y, output y staircases with x steps. For example:
f(3,1) - 1 staircase with 3 steps.
_
_|
_|
f(5,2) - 2 staircases with 5 steps.
...
16
votes
10answers
2k views
Print the QWERTY keyboard using keys that are as close together as possible
Normally, challenges are scored in bytes, or sometimes Levenshtein distance, but for this one we're using keyboard distance -- the number of keys between the keys used to type the program (use the ...
21
votes
10answers
2k views
Chaining Programs
Challenge
In this challenge, you will be writing the first program, p1, of an infinite sequence of programs, in which running pn outputs/generates program pn+1. When concatenating the first n >= 2 ...
4
votes
18answers
389 views
Maximizing output from minimal input
Obviously, code golfing is all about making the most of the least code. Who really cares what the actual output is?
While we have had a challenge for highest input-to-output ratio, this is a call for ...
12
votes
4answers
542 views
An executable script file that runs on POSIX and Windows
Challenge: write a single script file foo.cmd which can be invoked from the vanilla Windows cmd.exe prompt (not PowerShell, not in administrator mode), to execute arbitrary Windows-specific code...
...
4
votes
0answers
147 views
Finding the smallest grid of squares [closed]
Inspiration from Puzzling.SE.
Suppose we have an m × n grid such that each element is a base 10 digit. We can read the numbers from such a grid so that we fix a starting element, go to one of the ...
26
votes
10answers
1k views
Find the largest gap between good primes
Following the fine tradition of questions such as Find the largest prime whose length, sum and product is prime , this is a variant on a largest prime challenge.
Input
Your code should not take any ...
51
votes
23answers
5k views
The versatile integer printer
Write a piece of code that is executable in at least three different languages. The code must output the integer 1 in language number one, 2 in language number two, 3 in language number three etc.
...
7
votes
3answers
196 views
Guess the hidden communities
Background
This challenge is about the stochastic block model.
Basically, you are given an undirected graph, where the nodes represent people, and the edges represent social connections between them.
...
-2
votes
1answer
86 views
Creating a colour chart in PHP will all colours [duplicate]
Now, before we begin, this has already been done here. But!, there are no PHP answers.
With that in mind, my CodeGolf is thus: create a program to show all the colours in the html CSS spectrum using ...
-4
votes
1answer
203 views
Check my program! [closed]
Challenge
Make an error-checker in the least amount of possible bytes! If you received an HTML program as a string through standard input, your program will be able to find all the errors and return ...
2
votes
1answer
193 views
Quine Pride Parade!
These days, I watched on TV a Gay Pride parade; at the time, I was thinking about quines and how they're a bit queer, outputting themselves (out of the closet?) and, well, why not combine both things ...
17
votes
7answers
539 views
Finding sum-free partitions
Executive summary
Given input k, find a partition of integers 1 to n into k sum-free subsets for the largest n you can within 10 minutes.
Background: Schur numbers
A set A is sum-free if its ...
13
votes
3answers
663 views
An optimization challenge with strange coins
You have n coins which each weigh either -1 or 1. Each is labelled from 0 to n-1 so you can tell the coins apart. You have one (magic) weighing device as well. At the first turn you can put as many ...
15
votes
6answers
401 views
Who's that probability distribution?
Introduction
In this challenge, you are given a list of nonnegative floating point numbers drawn independently from some probability distribution.
Your task is to infer that distribution from the ...
11
votes
3answers
201 views
Fit the factors in the field
Given a positive integer below 1000, display all possible rectangles with that area.
Task
Let's say the input is 20. We can make a rectangle 20×1, 10×2, or 5×4, so this is a valid output:
...
9
votes
1answer
409 views
Variant of racetrack with exact finishing point and zero terminal velocity
Introduction
The challenge is a very interesting variant of the game racetrack and those two challenges:
To Vectory! – The Vector Racing Grand Prix
Program a Racing Car
Source of this ...
2
votes
9answers
1k views
How's your string theory?
Back to the basics! You're in you comp sci class again, except wiser and golfier. You have the tools, you have the power… but do you have the skill? Probably.
Crash Course for the non-Computer ...
6
votes
5answers
417 views
Remove Whitespace from a Java Program [closed]
In this challenge, you will be given the source code of a Java program. Your task is to write a function or full program that will remove the whitespace from this program. The whitespace-removed ...
0
votes
0answers
132 views
Optimizing View Counts
Objective
You run a video site like YouTube or Vimeo. Each video has a unique ID which is a 32-byte string containing any of the following characters: a-zA-Z0-9. You are tasked to perform view ...
2
votes
2answers
202 views
Greater Average Submatrix
Objective
Write a program in any language that reads a matrix from stdin in which all columns are space delimited and all rows are newline delimited. The program must output a sub matrix so as that ...
13
votes
1answer
316 views
Make a (software) modem!
Objective
Design a modulator/demodulator pair to accurately transmit data as quickly as possible over simulated plain old telephone service (POTS).
Steps
Generate some random (/dev/random or the ...
36
votes
26answers
3k views
Difference should make no difference
Your company lately hired a new bunch of extremely dedicated sysadmins. They feel that just watching computer screens is quite limiting (I mean, 60Hz refresh rate is just NOT enough), so they hooked ...
90
votes
35answers
5k views
Source code ecological footprint
You've just been hired by a German car manufacturing company. Your first task, as an engineer, is to write a program that computes the ecological footprint of ASCII strings.
The ecological footprint ...
8
votes
4answers
429 views
Write two programs that compresses and decompresses data
Challenge:
Create a program that compresses a semi-random string, and another program that decompresses it. The question is indeed quite similar to this one from 2012, but the answers will most ...
27
votes
7answers
2k views
Beatles Songs and Hexagons
Write two triangle (i.e. pyramid) shaped programs.
The first one should be an upwards pointing text triangle with a minimum base width of three characters. So it would have a structure like
X
XXX
...
34
votes
5answers
702 views
Overcoming cluster size
Fed up with the reliability of flash storage, you decided to store all your programs on one of those good old 1,440 KiB floppies. However, after copying not even 3,000 programs, the disk was full. ...
35
votes
22answers
3k views
Remapping ASCII
Challenge
Write a program that reorders the ASCII characters!
It should output a single string containing all of the printable ASCII characters exactly once. The first character of this string is ...
16
votes
4answers
2k views
Big big numbers
Whilst trying to golf several of my answers, I've needed to write large integers in as few characters as possible.
Now I know the best way to do that: I'll be getting you to be writing this program.
...
8
votes
10answers
1k views
A Program that Prints Programs
Challenge
Your goal is to write a program that prints another program.
That printed program should print another program, and the new program should print another program, until the end.
Rules
...
32
votes
106answers
3k views
Let's make a word-search!
In this challenge, we will together create a word-search containing many programs in different languages.
I have started us off with a grid of 60-by-25 blanks (·), some of which are replaced by the ...
13
votes
0answers
309 views
Radiation Hardened Quine
As you should (hopefully) know, a radiation hardened quine is a quine that you can remove any one character from and still print its original, pre-modified source. The thing is, with most of these you ...
11
votes
1answer
387 views
An optimization version of the Hadamard problem
First, some definitions.
A Hadamard matrix is a square matrix whose entries are either +1 or −1 and whose rows are mutually orthogonal. The Hadamard conjecture proposes that a Hadamard matrix of ...
19
votes
4answers
1k views
Golfing strings in Fourier
Challenge
Given a string as input, golf down the Fourier program which outputs that string.
In Fourier there is no easy way to output a string: you have to go through each character code and output ...
2
votes
0answers
123 views
Num of pyramids possible with given number of bricks [closed]
I encountered this question in an interview and could not figure it out. I believe it has a dynamic programming solution but it eludes me.
Given a number of bricks, output the total number of 2d ...
11
votes
1answer
475 views
Lossless English language text compression challenge [closed]
Challenge:
Your challenge (should you choose to accept it) is to compress and decompress the 5MB "Complete Works of William Shakespeare" as found here:
...
-2
votes
1answer
198 views
Ich ne know pas [closed]
Challenge
You must write a program which correctly identifies the language a passage is written in.
Rules
The passage will be a string passed to your program either via STDIN or function arguments.
...
1
vote
3answers
462 views
Brainf*** code golf challenge - write a Brainf*** program that searches for the first non-zero cell
The challenge is to write a brainf*** program that searches sequentially through memory for the first NON-zero cell.
The program should start somewhere in fairly low memory (there will probably be ...
5
votes
0answers
424 views
Take It or Leave It III: A Game Show for Computers
This is the third in a series of puzzles that I will be posting every Monday at Midnight PST, and the final variant of "Take It or Leave It".
The first puzzle is located Here
The second puzzle is ...
13
votes
4answers
401 views
Find the largest independent set in a high-dimensional lattice-like graph
For a given positive integer n, consider all binary strings of length 2n-1. For a given string S, let L be an array of length n which contains the count of the number of 1s in each substring of ...
4
votes
1answer
390 views
Reflections in Water [closed]
Take a string as input. This string can be as long as you'd like, however, it may only include letters and spaces––no numbers, punctuation, etc. When a word is passed into your function, an image will ...
20
votes
7answers
3k views
Take It or Leave It II: A Game Show for Computers
This is the second in a series of puzzles that I will be posting every Monday at Midnight PST. The first puzzle is located Here.
Context:
A reclusive billionaire has created a game show to ...
28
votes
5answers
2k views
Take It or Leave It: A Game Show for Computers
Context:
A reclusive billionaire has created a game show to attract the world's best and brightest programmers. On Mondays at the stroke of midnight, he chooses one person from a pool of ...
6
votes
1answer
301 views
Cross platform… You wish
Write a program that will produce differing behaviors on as many different platforms as you can. Each differing platform awards one point (including an initial platform, meaning you can't score less ...
-6
votes
6answers
163 views
Deep thought: Levenshtein distance [duplicate]
So, blatantly plagiarizing from inspired by this challenge and its sequel, I thought I'd add another.
The text to match:
What do you get when you multiply six by nine
The result your ...
3
votes
2answers
674 views
A Kingdom Hearts VGM challenge
I'm a huge video game music fan. One of my favorite OSTs is that from Kingdom Hearts, by Yoko Shimomura.
The challenge
Create a program or function that takes two arguments in any format: an ...
1
vote
0answers
94 views
Minimizing Covering Arrays
This is the followup question to this previous CodeGolf question about Covering Arrays (the details of what Covering Arrays are and how they are formatted at the NIST website are there).
In this ...
