Code challenges of all types. For questions about golfing, bowling, etc, use Q&A. For questions about this community, use Meta. To get feedback on a challenge before posting it, use Sandbox.
Filters (None)
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...
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...
Simple challenge: Read a byte, swap bit 7 with 0, 6 with 1, 5 with 2 and 4 with 3 and then output the byte. For example the byte 0b1001'1100 would turn into 0b0011'1001. Rules: Shortest code wi...
Given a chess board with some knights on it, say how many squares are neither attacked by a knight nor containing a knight. Input An 8 by 8 grid where each square is either a knight or empty T...
Many programming languages have the concept of keywords, special syntax items that are not just identifiers reserved by some library, but words reserved by the language itself. The challenge is to...
Given a string of printable ASCII characters, convert them all to lowercase, except not just the letters. ASCII characters that are letters have a bit in their binary representation that is 0 for ...
import requests import json import numpy as np import base64 import cv2 Replace this with the actual image path you want to test image_path = 'H_L_.jpg' Read and preprocess the image image ...
Challenge idea taken from: Eliseo D'Annunzio Task Provide code that evaluates to 0.5 numerically, i.e. the output must be recognized by your chosen language as a numeric value (Number, float, dou...
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...
Given a sequence of lower case letters, sort them into order of height. Heights The heights of letters are dependent on font, so for this challenge the height order to be used is as defined below...
Given a hinged tetromino, give it a unique, consistent label independent of location, rotation, and reflection. Tetrominoes A tetromino is a connected subset of the square tiling, composed of 4 s...
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...
The probability of rolling every number from 1 to 6 with $N$ six-sided dice. Input A positive integer $N$. Your code must work for inputs up to and including 10, but may crash, error, or give ...
You roll $N$ six-sided dice simultaneously. Your score is the highest number rolled. If you play this game many times, what is the expected value (mean) of your score? Input A positive integer ...
Challenge This is a simple randomness challenge: Given a non-negative integer $n$, and positive integer $m$, simulate rolling and summing the results of $n$ fair dice, each of which have $m$ sides...
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...
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...
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...
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...
Connect opposite corners of a rectangle of characters without putting 4 characters in a row. Input Two numbers, W and H, representing the width and height of the rectangle Each number will be ...
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...
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...
Challenge A simple challenge: Given a two-dimensional matrix (an array of arrays) of real numbers, compute the determinant. The determinant of a matrix is a mathematical construct used in many ap...
The problem Someone has created an encoding format for square bit matrices, however they have found it isn't perfect! One encoding may not decode to exactly one matrix, or it may not even be possi...
This is a fixed output challenge. Output a textual representation of a chessboard hosting 8 queens, none of which are attacking each other. There are 92 ways of arranging them, 12 if rotations and...
Given a sequence of letters, omit those with the highest or lowest pop count. Terminology The pop count or population count of a binary string is the number of 1s in it. For this challenge, the ...
Given a string, convert all of its letters using ROT13, and all of its digits using ROT5. This is sometimes referred to as ROT13.5. Input A sequence of printable ASCII characters (character cod...
Convert a matrix or grid of digits to its antitranspose. For a square matrix , this is its reflection in its antidiagonal. More generally, for a rectangular matrix, this is its reflection in its sk...
Given a sequence of letters, output only the vowels. Input A sequence of letters This may be a string or any ordered data structure of characters (provided it is consistent between inputs) Th...
Given a radius R, output a text representation of a circle. Input A positive integer R (strictly greater than zero) You do not need to handle values of R greater than 32 Output A square ...
Given a word that can be rotated by 180 degrees (a half turn) about at least one of its 3 axes and continue to be composed of English alphabet letters, output one of its rotated forms. The 3 rotat...
Given an integer $N$ in balanced quinary, output the first $N$ characters of your source code if $N$ is positive, or the last $-N$ characters of your source code if $N$ is negative. Terminology ...
Challenge Given a string, e.g. Hello, do the following: Mirror it: Hello -> HelloolleH and create a right triangle using it as the sides: H ee l l l l o...
Given a positive integer as input, indicate which base from 2 to 16 gives the most holes in the representation of the input in that base. The digits used are 0123456789ABCDEF. Note that these incl...
Given a grid of numbers, mark the concentric areas around nonzero elements (beacons) decreasing from the value of the beacon till 1. For example, here are some grids with a single beacon: Size 1:...
An integer is called square-free if it is not a multiple of a perfect square other than 1. For example, 42 is square-free, but 44 is not because it is a multiple of the perfect square 4 = 2². Your...
A chequer board (also spelt "checker board" in some places) is an 8 by 8 grid of squares alternating between 2 colours. Check whether a provided pattern could be a region of a chequer board. The c...
Take an input string representing a number and convert it to decimal (base 10). However, the base of the input is not specified. Assume the input is in the smallest base for which its digits are va...
Challenge Given an array in any suitable format, create a frequency table for it. i.e: Pair each unique element with the number of times it appears in the array. You can return the frequency tabl...
This challenge is based on the i. verb from J. A range grid is basically a range of m × n numbers fit into a rectangular grid with m rows and n columns. A 2×3 range grid would be: 0 1 2 3 4 5 ...
Challenge A Niven number is a positive integer which is divisible by the sum of its digits. For example, 81 -> 8+1=9 -> 81%9=0. Your task is to find the first n Niven numbers, given n. Te...
Multiply complex numbers. 2 space-seperated ones will be input, as follows: (update: you can replace i with j or some other symbol if needed) a+bi -a+bi a-bi -a-bi where a and b are integers ...
Task I often need to find the factorial of a number or the sum of all numbers up to a number when cheating on math tests. To help me with this, your task is to write $F$, a generalized version of ...
Get ready for a comparatively dry question - this is intended to be one of the "the"s of the code-golfing dictionary. Create a program which inputs a base 10 non-negative whole number (without lea...
Description From the Esolangs wiki, In Fractran, a program consists of a finite list of positive, rational numbers. The input to a program is a positive integer n. The list is then searched ...
Create a program P1 which takes as input a base 10 number N1 (the numbers for the variables are important). Given N1, P1 will print a program P2. P2 will take as input a base 10 number N2 and outpu...
Challenge Given a list of integers >= 0 , check if all of them are equal. Tests [1,1,1,1,1] -> true [0,1,1,6,7] -> false [1] -> true [] -> undefined(you do n...
Goldbach's Conjecture states that every even whole number greater than 2 is the sum of 2 prime numbers. Your task is to return those 2 prime numbers, given an even whole number as input. There are ...
Introduction The Pell(no, not Bell) Numbers are a simple, Fibonacci-like sequence, defined by the following relation: $P_n=\begin{cases}0&\mbox{if }n=0;\\1&\mbox{if }n=1;\\2P_{n-1}+P_{n-2...
Challenge It's a bootstrapping challenge this time! Write a full program that, once run, writes the source code of another program that in turn, once run, writes the source code for another progra...
- ← Previous
- 1
- 2
- 3
- 4
- Next →
