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Racket track
Exercises
Exercises on the Racket track
Join the Racket Track
27 exercises to help you master Racket
easy
Hello World
The classical introductory exercise. Just say "Hello, World!"
strings
easy
All Your Base
Convert a number, represented as a sequence of digits in one base, to any other base.
integers
math
map
transforming
easy
Grains
Calculate the number of grains of wheat on a chessboard given that the number on each square doubles.
misc
easy
Two Fer
Create a sentence of the form "One for X, one for me."
optional values
text formatting
easy
Leap
Given a year, report if it is a leap year.
misc
easy
Difference Of Squares
Find the difference between the square of the sum and the sum of the squares of the first N natural numbers.
math
easy
Perfect Numbers
Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60 - 120 CE) classification scheme for natural numbers.
math
easy
Gigasecond
Given a moment, determine the moment that would be after a gigasecond has passed.
misc
easy
Bob
Bob is a lackadaisical teenager. In conversation, his responses are very limited.
misc
easy
Collatz Conjecture
Calculate the number of steps to reach 1 using the Collatz conjecture
math
easy
Hamming
Calculate the Hamming difference between two DNA strands.
misc
easy
Scrabble Score
Given a word, compute the scrabble score for that word.
misc
easy
Roman Numerals
Write a function to convert from normal numbers to Roman Numerals.
misc
easy
Meetup
Calculate the date of meetups.
conditionals
dates
parsing
pattern recognition
strings
easy
Anagram
Given a word and a list of possible anagrams, select the correct sublist.
misc
easy
RNA Transcription
Given a DNA strand, return its RNA Complement Transcription.
misc
easy
ETL
We are going to do the `Transform` step of an Extract-Transform-Load.
misc
easy
Word Count
Given a phrase, count the occurrences of each word in that phrase.
misc
easy
Phone Number
Clean up user-entered phone numbers so that they can be sent SMS messages.
misc
easy
Nucleotide Count
Given a DNA string, compute how many times each nucleotide occurs in the string.
misc
easy
Raindrops
Convert a number to a string, the contents of which depend on the number's factors.
misc
easy
Grep
Search a file for lines matching a regular expression pattern. Return the line number and contents of each matching line.
misc
easy
Say
Given a number from 0 to 999,999,999,999, spell out that number in English.
misc
easy
Allergies
Given a person's allergy score, determine whether or not they're allergic to a given item, and their full list of allergies.
misc
easy
List Ops
Implement basic list operations
misc
easy
Acronym
Convert a long phrase to its acronym
misc
medium
Affine Cipher
Create an implementation of the Affine cipher, an ancient encryption algorithm from the Middle East.
algorithms
cryptography
strings