Exercises on the Swift Track | Exercism

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Hello World

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

optional values

text formatting

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.

Gigasecond

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

Difference Of Squares

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

RNA Transcription

Given a DNA strand, return its RNA Complement Transcription.

Sum Of Multiples

Given a number, find the sum of all the multiples of particular numbers up to but not including that number.

Space Age

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

discriminated unions

floating point numbers

Bob

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

control flow if else statements

Grains

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

Hamming

Calculate the Hamming difference between two DNA strands.

Nucleotide Count

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

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.

Raindrops

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

text formatting

Grade School

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

ETL

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

Isogram

Determine if a word or phrase is an isogram.

List Ops

Implement basic list operations

functional programming

Clock

Implement a clock that handles times without dates.

structural equality

Triangle

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

discriminated unions

Robot Name

Manage robot factory settings.

Scrabble Score

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

Kindergarten Garden

Given a diagram, determine which plants each child in the kindergarten class is responsible for.

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.

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.

Sieve

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

Phone Number

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

Perfect Numbers

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

discriminated unions

Robot Simulator

Write a robot simulator.

Binary Search

Implement a binary search algorithm.

Flatten Array

Take a nested list and return a single list with all values except nil/null

Sublist

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

Secret Handshake

Given a decimal number, convert it to the appropriate sequence of events for a secret handshake.

bitwise operations

Collatz Conjecture

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

Diamond

Given a letter, print a diamond starting with 'A' with the supplied letter at the widest point.

ISBN Verifier

Check if a given string is a valid ISBN-10 number.

pattern matching

Protein Translation

Translate RNA sequences into proteins.

control flow conditionals

control flow loops

Circular Buffer

A data structure that uses a single, fixed-size buffer as if it were connected end-to-end.

control flow conditionals

control flow loops

data structures

exception handling

Scale Generator

Generate musical scales, given a starting note and a set of intervals.

pattern matching

Proverb

For want of a horseshoe nail, a kingdom was lost, or so the saying goes. Output the full text of this proverbial rhyme.

Word Count

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

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

Beer Song

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

Twelve Days

Output the lyrics to 'The Twelve Days of Christmas'

text formatting

Meetup

Calculate the date of meetups.

Anagram

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

Series

Given a string of digits, output all the contiguous substrings of length `n` in that string.

Simple Linked List

Write a simple linked list implementation that uses Elements and a List

Acronym

Convert a long phrase to its acronym

Matrix

Given a string representing a matrix of numbers, return the rows and columns of that matrix.

All Your Base

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

Largest Series Product

Given a string of digits, calculate the largest product for a contiguous substring of digits of length n.

House

Output the nursery rhyme 'This is the House that Jack Built'.

text formatting

Pythagorean Triplet

There exists exactly one Pythagorean triplet for which a + b + c = 1000. Find the product a * b * c.

Saddle Points

Detect saddle points in a matrix.

Pascal's Triangle

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

Prime Factors

Compute the prime factors of a given natural number.

Pangram

Determine if a sentence is a pangram.

Rotational Cipher

Create an implementation of the rotational cipher, also sometimes called the Caesar cipher.

Say

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

text formatting

Roman Numerals

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

Binary Search Tree

Insert and search for numbers in a binary tree.

OCR Numbers

Given a 3 x 4 grid of pipes, underscores, and spaces, determine which number is represented, or whether it is garbled.

pattern recognition

Linked List

Implement a doubly linked list

Simple Cipher

Implement a simple shift cipher like Caesar and a more secure substitution cipher

Atbash Cipher

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

Food Chain

Generate the lyrics of the song 'I Know an Old Lady Who Swallowed a Fly'

text formatting

Custom Set

Create a custom set type.

Crypto Square

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

Luhn

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

Run Length Encoding

Implement run-length encoding and decoding.

Tournament

Tally the results of a small football competition.

text formatting

Bowling

Score a bowling game

Nth Prime

Given a number n, determine what the nth prime is.

Palindrome Products

Detect palindrome products in a given range.

Pig Latin

Implement a program that translates from English to Pig Latin

Transpose

Take input text and output it transposed.

Complex Numbers

Implement complex numbers.

Bracket Push

Minesweeper

Add the numbers to a minesweeper board

Dominoes

Make a chain of dominoes.

Wordy

Parse and evaluate simple math word problems returning the answer as an integer.

Poker

Pick the best hand(s) from a list of poker hands.

discriminated unions