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CoffeeScript track
Exercises
Exercises on the CoffeeScript track
Join the CoffeeScript Track
21 exercises to help you master CoffeeScript
easy
Hello World
The classical introductory exercise. Just say "Hello, World!"
conditionals
control flow if statements
optional values
text formatting
medium
Bob
Bob is a lackadaisical teenager. In conversation, his responses are very limited.
conditionals
control flow switch
text formatting
easy
Word Count
Given a phrase, count the occurrences of each word in that phrase.
maps
strings
text formatting
transforming
variables
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.
arrays
maps
transforming
easy
Binary
Convert a binary number, represented as a string (e.g. '101010'), to its decimal equivalent using first principles
integers
transforming
math
easy
Anagram
Given a word and a list of possible anagrams, select the correct sublist.
sorting
strings
text formatting
easy
Trinary
Convert a trinary number, represented as a string (e.g. '102012'), to its decimal equivalent using first principles.
integers
transforming
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).
integers
transforming
math
easy
Triangle
Determine if a triangle is equilateral, isosceles, or scalene.
arrays
equality
easy
Luhn
Given a number determine whether or not it is valid per the Luhn formula.
algorithms
arrays
integers
pattern recognition
medium
Binary Search Tree
Insert and search for numbers in a binary tree.
algorithms
arrays
integers
trees
medium
Nth Prime
Given a number n, determine what the nth prime is.
arrays
filter
loops
map
math
easy
Palindrome Products
Detect palindrome products in a given range.
arrays
integers
math
easy
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.
algorithms
arrays
games
logic
medium
Wordy
Parse and evaluate simple math word problems returning the answer as an integer.
integers
pattern recognition
regular expressions
strings
easy
Clock
Implement a clock that handles times without dates.
integers
loops
text formatting
easy
Beer Song
Produce the lyrics to that beloved classic, that field-trip favorite: 99 Bottles of Beer on the Wall.
control flow switch
loops
text formatting
medium
Atbash Cipher
Create an implementation of the atbash cipher, an ancient encryption system created in the Middle East.
arrays
cryptography
strings
text formatting
easy
Linked List
Implement a doubly linked list
algorithms
classes
object oriented programming
variables
easy
Pascal's Triangle
Compute Pascal's triangle up to a given number of rows.
algorithms
arrays
integers
math
easy
Nucleotide Count
Given a DNA string, compute how many times each nucleotide occurs in the string.
filtering
maps
strings