Exercises on the Common Lisp Track | Exercism

Hello World

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

Two Fer

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

optional values

text formatting

Hamming

Calculate the Hamming difference between two DNA strands.

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

Leap

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

Anagram

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

Beer Song

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

text formatting

Roman Numerals

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

text formatting

Word Count

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

Bob

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

Luhn

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

All Your Base

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

Acronym

Convert a long phrase to its acronym

Twelve Days

Output the lyrics to 'The Twelve Days of Christmas'

Sublist

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

Grains

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

Gigasecond

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

Robot Name

Manage robot factory settings.

Raindrops

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

Grade School

Given students' names along with the grade that they are in, create a roster for the school

Phone Number

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

ETL

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

Space Age

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

floating point numbers

Nucleotide Count

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

Collatz Conjecture

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

Perfect Numbers

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

Isogram

Determine if a word or phrase is an isogram.

Meetup

Calculate the date of meetups.

Triangle

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

floating point numbers

Difference Of Squares

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

floating point numbers

Scrabble Score

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

Binary

Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles

bitwise operations

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

text formatting

Sieve

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

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.

Atbash Cipher

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

Prime Factors

Compute the prime factors of a given natural number.

Crypto Square

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

Trinary

Convert a trinary number, represented as a string (e.g. '102012'), to its decimal equivalent using first principles.

Pascal's Triangle

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

Armstrong Numbers

Determine if a number is an Armstrong number

Robot Simulator

Write a robot simulator.