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Clojure track
Exercises
Exercises on the Clojure track
Join the Clojure Track
76 exercises to help you master Clojure
easy
Hello World
The classical introductory exercise. Just say "Hello, World!"
misc
easy
Two Fer
Create a sentence of the form "One for X, one for me."
misc
easy
Reverse String
Reverse a string
misc
easy
Bob
Bob is a lackadaisical teenager. In conversation, his responses are very limited.
misc
easy
Armstrong Numbers
Determine if a number is an Armstrong number
math
easy
RNA Transcription
Given a DNA strand, return its RNA Complement Transcription.
misc
easy
Run Length Encoding
Implement run-length encoding and decoding.
misc
easy
ISBN Verifier
Check if a given string is a valid ISBN-10 number.
misc
easy
Word Count
Given a phrase, count the occurrences of each word in that phrase.
misc
easy
Anagram
Given a word and a list of possible anagrams, select the correct sublist.
misc
easy
Say
Given a number from 0 to 999,999,999,999, spell out that number in English.
misc
easy
Beer Song
Produce the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.
misc
easy
Collatz Conjecture
Calculate the number of steps to reach 1 using the Collatz conjecture
math
easy
Series
Given a string of digits, output all the contiguous substrings of length `n` in that string.
misc
easy
Nucleotide Count
Given a DNA string, compute how many times each nucleotide occurs in the string.
misc
easy
Hamming
Calculate the Hamming difference between two DNA strands.
misc
easy
Phone Number
Clean up user-entered phone numbers so that they can be sent SMS messages.
misc
medium
Clock
Implement a clock that handles times without dates.
misc
easy
Grade School
Given students' names along with the grade that they are in, create a roster for the school
misc
easy
Complex Numbers
Implement complex numbers.
math
easy
Robot Name
Manage robot factory settings.
misc
easy
Leap
Given a year, report if it is a leap year.
misc
easy
ETL
We are going to do the `Transform` step of an Extract-Transform-Load.
misc
easy
Flatten Array
Take a nested list and return a single list with all values except nil/null
misc
easy
Sublist
Write a function to determine if a list is a sublist of another list.
misc
easy
Binary Search
Implement a binary search algorithm.
misc
easy
Perfect Numbers
Determine if a number is perfect, abundant, or deficient based on Nicomachus' (60 - 120 CE) classification scheme for natural numbers.
math
medium
Meetup
Calculate the date of meetups.
misc
easy
Space Age
Given an age in seconds, calculate how old someone is in terms of a given planet's solar years.
misc
easy
Grains
Calculate the number of grains of wheat on a chessboard given that the number on each square doubles.
misc
easy
Gigasecond
Given a moment, determine the moment that would be after a gigasecond has passed.
misc
easy
Triangle
Determine if a triangle is equilateral, isosceles, or scalene.
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
Binary
Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles
math
easy
Trinary
Convert a trinary number, represented as a string (e.g. '102012'), to its decimal equivalent using first principles.
math
medium
Spiral Matrix
Given the size, return a square matrix of numbers in spiral order.
recursivity
easy
Prime Factors
Compute the prime factors of a given natural number.
math
easy
Raindrops
Convert a number to a string, the content of which depends on the number's factors.
misc
medium
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
medium
Octal
Convert a octal number, represented as a string (e.g. '1735263'), to its decimal equivalent using first principles (i.e. no, you may not use built-in or external libraries to accomplish the conversion).
math
easy
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.
misc
easy
Atbash Cipher
Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.
misc
medium
Bank Account
Simulate a bank account supporting opening/closing, withdraws, and deposits of money. Watch out for concurrent transactions!
misc
medium
Crypto Square
Implement the classic method for composing secret messages called a square code.
misc
easy
Pascal's Triangle
Compute Pascal's triangle up to a given number of rows.
math
easy
Sum Of Multiples
Given a number, find the sum of all the multiples of particular numbers up to but not including that number.
math
medium
Sieve
Use the Sieve of Eratosthenes to find all the primes from 2 up to a given number.
math
medium
Luhn
Given a number determine whether or not it is valid per the Luhn formula.
misc
easy
Kindergarten Garden
Given a diagram, determine which plants each child in the kindergarten class is responsible for.
misc
medium
Robot Simulator
Write a robot simulator.
misc
medium
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.
misc
easy
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.
misc
easy
Binary Search Tree
Insert and search for numbers in a binary tree.
misc
medium
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
Hexadecimal
Convert a hexadecimal number, represented as a string (e.g. "10af8c"), to its decimal equivalent using first principles (i.e. no, you may not use built-in or external libraries to accomplish the conversion).
math
easy
All Your Base
Convert a number, represented as a sequence of digits in one base, to any other base.
math
medium
Largest Series Product
Given a string of digits, calculate the largest product for a contiguous substring of digits of length n.
math
hard
POV
Reparent a graph on a selected node
misc
medium
Matching Brackets
Make sure the brackets and braces all match.
misc
medium
Minesweeper
Add the numbers to a minesweeper board
misc
easy
Change
Correctly determine change to be given using the least number of coins
misc
easy
Pangram
Determine if a sentence is a pangram.
misc
medium
Wordy
Parse and evaluate simple math word problems returning the answer as an integer.
misc
easy
Isogram
Determine if a word or phrase is an isogram.
misc
easy
Acronym
Convert a long phrase to its acronym
misc
easy
Nth Prime
Given a number n, determine what the nth prime is.
math
easy
Pig Latin
Implement a program that translates from English to Pig Latin
misc
easy
Secret Handshake
Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.
misc
easy
Rotational Cipher
Create an implementation of the rotational cipher, also sometimes called the Caesar cipher.
misc
medium
Diamond
Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.
misc
easy
Protein Translation
Translate RNA sequences into proteins.
pattern matching
strings
easy
Proverb
For want of a horseshoe nail, a kingdom was lost, or so the saying goes. Output the full text of this proverbial rhyme.
misc
medium
Poker
Pick the best hand(s) from a list of poker hands.
misc
medium
Dominoes
Make a chain of dominoes.
misc
hard
Go Counting
Count the scored points on a Go board.
misc