Exercises on the Bash Track | Exercism

Exercism v3 launches on Sept 1st 2021. Learn more! 🚀🚀🚀

Hello World

The classical introductory exercise. Just say "Hello, World!"

Two Fer

Create a sentence of the form "One for X, one for me."

control flow conditionals

text formatting

Error Handling

Implement various kinds of error handling and resource management

input validation

Raindrops

Convert a number to a string, the content of which depends on the number's factors.

control flow conditionals

input validation

Hamming

Calculate the Hamming difference between two DNA strands.

control flow loops

string comparison

Acronym

Convert a long phrase to its acronym

input validation

string transformation

Armstrong Numbers

Determine if a number is an Armstrong number

Pangram

Determine if a sentence is a pangram.

string transformation

Bob

Bob is a lackadaisical teenager. In conversation, his responses are very limited.

control flow conditionals

Scrabble Score

Given a word, compute the Scrabble score for that word.

Grains

Calculate the number of grains of wheat on a chessboard given that the number on each square doubles.

control flow conditionals

input validation

Reverse String

Reverse a string

Difference Of Squares

Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.

control flow conditionals

control flow loops

Leap

Given a year, report if it is a leap year.

control flow conditionals

input validation

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

associative arrays

control flow loops

Anagram

Given a word and a list of possible anagrams, select the correct sublist.

control flow conditionals

control flow loops

string transformation

Collatz Conjecture

Calculate the number of steps to reach 1 using the Collatz conjecture

control flow conditionals

input validation

Nucleotide Count

Given a DNA string, compute how many times each nucleotide occurs in the string.

control flow loops

string comparison

Phone Number

Clean up user-entered phone numbers so that they can be sent SMS messages.

control flow conditionals

string comparison

string transformation

Triangle

Determine if a triangle is equilateral, isosceles, or scalene.

input validation

number comparison

Word Count

Given a phrase, count the occurrences of each word in that phrase.

control flow loops

string comparison

Gigasecond

Given a moment, determine the moment that would be after a gigasecond has passed.

Luhn

Given a number determine whether or not it is valid per the Luhn formula.

control flow conditionals

Atbash Cipher

Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.

pattern matching

Roman Numerals

Write a function to convert from normal numbers to Roman Numerals.

Affine Cipher

Create an implementation of the Affine cipher, an ancient encryption algorithm from the Middle East.

Isogram

Determine if a word or phrase is an isogram.

Diamond

Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.

string transformation

ISBN Verifier

Check if a given string is a valid ISBN-10 number.

string transformation

All Your Base

Convert a number, represented as a sequence of digits in one base, to any other base.

Allergies

Given a person's allergy score, determine whether or not they're allergic to a given item, and their full list of allergies.

bitwise operations

Beer Song

Produce the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.

text formatting

control flow loops

Food Chain

Generate the lyrics of the song 'I Know an Old Lady Who Swallowed a Fly'

text formatting

control flow loops

Forth

Implement an evaluator for a very simple subset of Forth

control flow conditionals

input validation

string comparison

Resistor Color Duo

Convert color codes, as used on resistors, to a numeric value.

control flow conditionals

Resistor Color Trio

Convert color codes, as used on resistors, to a human-readable label.

control flow conditionals

Binary Search

Implement a binary search algorithm.

Say

Given a number from 0 to 999,999,999,999, spell out that number in English.

text formatting

Space Age

Given an age in seconds, calculate how old someone is in terms of a given planet's solar years.

Matching Brackets

Make sure the brackets and braces all match.

control flow loops

House

Output the nursery rhyme 'This is the House that Jack Built'.

control flow conditionals

Proverb

For want of a horseshoe nail, a kingdom was lost, or so the saying goes. Output the full text of this proverbial rhyme.

text formatting

control flow loops

Twelve Days

Output the lyrics to 'The Twelve Days of Christmas'

text formatting

control flow loops

Change

Correctly determine change to be given using the least number of coins

Grep

Search a file for lines matching a regular expression pattern. Return the line number and contents of each matching line.

regular expressions

Diffie Hellman

Diffie-Hellman key exchange.

Two Bucket

Given two buckets of different size, demonstrate how to measure an exact number of liters.

associative arrays

control flow conditionals

Pig Latin

Implement a program that translates from English to Pig Latin

regular expressions

Prime Factors

Compute the prime factors of a given natural number.

control flow conditionals

control flow loops

Run Length Encoding

Implement run-length encoding and decoding.

string transformation

Secret Handshake

Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.

bitwise operations

Series

Given a string of digits, output all the contiguous substrings of length `n` in that string.

Sieve

Use the Sieve of Eratosthenes to find all the primes from 2 up to a given number.

control flow conditionals

Rotational Cipher

Create an implementation of the rotational cipher, also sometimes called the Caesar cipher.

string transformation

associative arrays

Largest Series Product

Given a string of digits, calculate the largest product for a contiguous substring of digits of length n.

control flow loops

Yacht

Score a single throw of dice in the game Yacht

Rational Numbers

Implement rational numbers.

Perfect Numbers

Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60 - 120 CE) classification scheme for positive integers.

Protein Translation

Translate RNA sequences into proteins.

associative arrays

control flow loops

Sum Of Multiples

Given a number, find the sum of all the multiples of particular numbers up to but not including that number.

control flow loops

Pascal's Triangle

Compute Pascal's triangle up to a given number of rows.

text formatting

Bowling

Score a bowling game

Kindergarten Garden

Given a diagram, determine which plants each child in the kindergarten class is responsible for.

Palindrome Products

Detect palindrome products in a given range.

Nth Prime

Given a number n, determine what the nth prime is.

Wordy

Parse and evaluate simple math word problems returning the answer as an integer.

control flow loops

Simple Cipher

Implement a simple shift cipher like Caesar and a more secure substitution cipher

Variable Length Quantity

Implement variable length quantity encoding and decoding.

base conversion

bitwise operations

Pythagorean Triplet

There exists exactly one Pythagorean triplet for which a + b + c = 1000. Find the product a * b * c.

control flow conditionals

control flow loops

Markdown

Refactor a Markdown parser

control flow conditionals

control flow loops

text formatting

OCR Numbers

Given a 3 x 4 grid of pipes, underscores, and spaces, determine which number is represented, or whether it is garbled.

input validation

string transformation

Transpose

Take input text and output it transposed.

string transformation

Robot Simulator

Write a robot simulator.

control flow conditionals

control flow loops

input validation

Tournament

Tally the results of a small football competition.

text formatting

Spiral Matrix

Given the size, return a square matrix of numbers in spiral order.

control flow loops

text formatting

Clock

Implement a clock that handles times without dates.

text formatting

Sublist

Write a function to determine if a list is a sublist of another list.

Meetup

Calculate the date of meetups.

control flow conditionals

external commands

D&D Character

Randomly generate Dungeons & Dragons characters

Knapsack

Given a knapsack that can only carry a certain weight, determine which items to put in the knapsack in order to maximize their combined value.

control flow loops

Queen Attack

Given the position of two queens on a chess board, indicate whether or not they are positioned so that they can attack each other.

control flow conditionals

input validation

Poker

Pick the best hand(s) from a list of poker hands.

control flow conditionals

Rail Fence Cipher

Implement encoding and decoding for the rail fence cipher.

control flow conditionals

control flow loops

input validation

Crypto Square

Implement the classic method for composing secret messages called a square code.

Rectangles

Count the rectangles in an ASCII diagram.

control flow conditionals

control flow loops

Darts

Write a function that returns the earned points in a single toss of a Darts game

control flow conditionals

Satellite

Rebuild binary trees from pre-order and in-order traversals.

input validation

Square Root

Given a natural radicand, return its square root.