Exercises on the Racket Track | Exercism

Hello World

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

Reverse String

Reverse a string

All Your Base

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

Grains

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

Two Fer

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

optional values

text formatting

Leap

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

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 natural numbers.

Armstrong Numbers

Determine if a number is an Armstrong number

Gigasecond

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

Bob

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

Collatz Conjecture

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

Hamming

Calculate the Hamming difference between two DNA strands.

Scrabble Score

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

Roman Numerals

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

Meetup

Calculate the date of meetups.

pattern recognition

Anagram

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

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

ETL

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

Word Count

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

Isogram

Determine if a word or phrase is an isogram.

Phone Number

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

Nucleotide Count

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

Raindrops

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

Grep

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

Say

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

Allergies

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

List Ops

Implement basic list operations

Acronym

Convert a long phrase to its acronym

Affine Cipher

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

Atbash Cipher

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