Exercises on the Groovy Track | Exercism

🎉 Exercism Research is now launched. Help Exercism, help science and have some fun at research.exercism.io 🎉

Hello World

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

Raindrops

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

Isogram

Determine if a word or phrase is an isogram.

Anagram

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

Two Fer

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

Reverse String

Reverse a string

Resistor Color

Convert a resistor band's color to its numeric representation

Darts

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

Protein Translation

Translate RNA sequences into proteins.

Proverb

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

Bob

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

Hamming

Calculate the Hamming difference between two DNA strands.

Accumulate

Implement the `accumulate` operation, which, given a collection and an operation to perform on each element of the collection, returns a new collection containing the result of applying that operation to each element of the input collection.

Strain

Implement the `keep` and `discard` operation on collections. Given a collection and a predicate on the collection's elements, `keep` returns a new collection containing those elements where the predicate is true, while `discard` returns a new collection containing those elements where the predicate is false.

Resistor Color Duo

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

ISBN Verifier

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

Luhn

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

type conversion

Phone Number

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

regular expressions

pattern matching

Nucleotide Count

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

exception handling

Series

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

type conversion

Roman Numerals

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

Gigasecond

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

Resistor Color Trio

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

Leap

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

Allergies

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

Scrabble Score

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

pattern matching

Difference Of Squares

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

Perfect Numbers

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

exception handling

Sum Of Multiples

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

Secret Handshake

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

bitwise operations

Matrix

Given a string representing a matrix of numbers, return the rows and columns of that matrix.

pattern matching

type conversion

Triangle

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

exception handling

Collatz Conjecture

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

exception handling

Nth Prime

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

exception handling

Prime Factors

Compute the prime factors of a given natural number.

Rotational Cipher

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

Atbash Cipher

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

Run Length Encoding

Implement run-length encoding and decoding.

pattern matching

Saddle Points

Detect saddle points in a matrix.

All Your Base

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

exception handling

Flatten Array

Take a nested list and return a single list with all values except nil/null

Matching Brackets

Make sure the brackets and braces all match.

Word Count

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

ETL

We are going to do the `Transform` step of an Extract-Transform-Load.

Robot Name

Manage robot factory settings.

pattern matching

regular expressions

text formatting

Binary Search

Implement a binary search algorithm.

Bank Account

Simulate a bank account supporting opening/closing, withdraws, and deposits of money. Watch out for concurrent transactions!

exception handling

Linked List

Implement a doubly linked list

Armstrong Numbers

Determine if a number is an Armstrong number

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

Pangram

Determine if a sentence is a pangram.

pattern matching

regular expressions

Space Age

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

floating point numbers

Acronym

Convert a long phrase to its acronym

Grains

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

High Scores

Manage a player's High Score list