# Posts by WheatWizard

You are a low-level censor working for the Ministry of Media Accuracy. Part of your job is to make sure that certain words don't appear in publications. Every morning you get a fresh stack of next...

Task Given a list of numbers $X$ produce a second list of numbers $Y$ such that $Y_i$ is the length of the longest common prefix of $X$ and $X$ with the first $i$ elements removed. For example if...

Given a list of non-negative integers the function $f$ replaces every integer with the number of identical integers preceding it (not necessarily contiguously). So f [1,1,2,2,1,3,3] = [1,2,1,2,3,1...

You work at a beach. In the afternoon, the sun gets quite hot and beachgoers want to be shaded. So you put out umbrellas. When you put out umbrellas you want to shade the entire beach, with as few ...

An polyomino is a non-empty connected subset of the square tiling consisting of squares joined along their edges. We will not require that polyominos be simply connected, that is they can have hole...

In this challenge you will take an Irish word and a personal pronoun and create the possessive pronoun construction combining the two. For example sé, madra becomes a mhadra. Translated to English...

You work in a kitchen which has a peculiar rule. When you mix something into a pot you must always add at least one new ingredient. So you can add pasta, oil, salt then pesto, but not pasta, pesto...

The Universal Crossword has a set of guidelines for crossword puzzle submissions. In this challenge we are going to be concerned with their rules for hidden word themes. A hidden word clue consis...

Given a number $n \geq 3$ as input output the smallest number $k$ such that the modular residues of $k$ by the first $n$ primes is exactly $\{-1,0,1\}$. That is there is a prime in the first $n$ p...

Given two binary strings $A$ and $B$ such that $A$ is an anagram of $B$, output a third binary string $S$ such that both $A$ and $B$ can be created by iterated removals of the substring $10101$ fro...

Task You are going to take three strings as input $A$, $B$ and $X$. And your goal is to determine if there exists a third string $S$ such that both $A$ and $B$ can be formed by iteratively removin...

In this challenge you will take a number $n$ and a string $X$ of length $\geq n$, and produce a regular expression which matches all strings that are withing $n$ character substitutions of $X$. Sp...

Haskell + hgl, 14 bytes xBl<<ss><fn<iw Attempt This Online! Explanation ss gets all substrings of the input fn filters out the substrings that don't ... iw checks if the fo...

I'm going to reiterate and build off ideas I laid out on this post on PPCG. First let's point out that at current the leader board does not support fractional scores. In this answer I am going to ...

Haskell + hgl, 134 bytes k=cy"X.XX" x#1=[4,0,9,9]!x 2#y=8 3#y=[8,9,4,4]!y x#3=[0,3]!x _#_=0 x?y|(n,j)<-fvD 4$x%4#(y%4)=tk y$dr j$tk x<dr n<cy[dr2 k,k,cy".X",k] Attempt This Onlin...

An $n$-polyomino is a connected subset of the square tiling consisting of $n$ squares. We will not require that polyominos be simply connected, that is they can have holes. We will say a $n$-polyo...

Haskell + hgl, 30 bytes ic"|"<<tv(:".")><fl<ce '.'><eq Attempt This Online! Explanation This performs a cartesian product to get all possible ways to replace characters w...

At my job we have to sometimes lay out materials. Materials come in large long rolls and are cut into smaller pieces when being laid out. When we order the rolls we draw up a layout document which...

Your task is to write a program $p$ which outputs a string $s$ with the same length as $p$, where $s \neq p$. If I remove the $n$th byte from your program to get program $q$, then either $q$ outpu...

Recently I asked for tips on improving some code-golf of mine. The code was supposed to output every third value of the Fibonacci sequence starting with 2: 2,8,34,144,610,2584,10946,46368,196418,...

Haskell + hgl, 10 bytes mpn$ce~<gj Attempt This Online! Explanation mpn map across all non-empty prefixes of the input ... ce count the number of elements in each prefix equal to ... g...