Congratulations ! You've just been hired by the Nasa to work on the new Horizons 2 project. Sadly, there had been huge budget cutbacks recently, so the top management has decided to fake the whole planned Pluto flyby (as they did for the moon landings in the 70s). Your task is to write a progra...

The Banach–Tarski Paradox ascii-art, grid, code-challenge The Banach–Tarski paradox states that, given a 3‑dimensional sphere, you can decompose the sphere into a finite number of point subsets. These disjoint sets of points can then be reassembled in a different way to produce a copy of the ...

In this meta.codegolf sandbox question, the following shape is misaligned: ########## ###@%$*.&.%%!### ##!$,%&?,?*?.*@~## ##&**!,$%$@@?@*@&&## #@&$?@!%$*%,.?@?.@&@,# #,..,.$&*?!$$@%%,**&&# ##.!?@*.%?!*&$!%&?## ##!&?$?&.!,?!&!%## ###,@$*&@*,%*### ########## It looks fine...

This challenge is a slightly different kind of Code Golf challenge. Rather than coding to match IO, you code to match an interface. Background Finite state machines are very useful design models for modeling event-based programming. A state machine is defined by a set of states and tranitions b...

Given a dictionary file (a text file containing a word or phrase on each line, with possible punctuation but no numbers; every line is alphabetized), you must output each combination of words where one letter can be removed from a word to make another; the removed letter should be encased in pare...

A Hundred Squares! Back to basics... code-golfarithmetic As a teacher at the local primary (grade?) school, you need a way to teach your class their times tables. At your disposal, you have hundred squares and red pens. You need to also be able to show your class the correct answers quickly. ...

The shortest code for testing reliable password ( for Vault Password Rank 3 puzzle ) Introduction I started playing Empire of Code recently, and there was some challenge. The player is supposed to write a code on a python or on javascript to detect if passed string is reliable password, that is...

It was recently suggested in a comment to point at our standard loopholes (and potentially other implicit community rules) next to the Answer text area (similar to the How to ask? sidebar when writing a question): Wouldn't there be a way to customize the "answer" box so that there is a warnin...

Easily modifiable code Although there are real world applications for both golfing and speed optimisation, much of modern software is instead optimised for maintenance. It is designed to be easy to modify. Your objective is to write 3 pieces of code, 1 for each of the following 3 tasks. Task ...

In Lisp style languages, a list is usually defined like this: (list 1 2 3) For the purposes of this challenge, all lists will only contain positive integers or other lists. We will also leave out the list keyword at the start, so the list will now look like this: (1 2 3) We can get the firs...

PPCG New Question Generator code-golf Specification Write a program that does the following, given a string s and an integer n (as a file, STDIN, or command line arguments): Determines the n most used characters in that quote. If there are two characters that are equally used, the character ...

One of the reasons I've always loved Pokemon is because for such a simple-seeming game, it has so many layers of complexity. Let's consider the move Hidden Power. In game, the type and power (at least before Generation VI) of Hidden Power is different for every Pokemon that uses it! That's pretty...