### Add new Swift exercises

One of the easiest ways to add new exercises to the Swift track is to translate them from other language tracks on Exercism. This page lists all of the problem specifications in the common pool of exercises which have not yet been implemented in Swift.

The icon links to the language-independent description of the problem.

The icon links to the canonical test data.

We also link to all the implementations of each exercise in other languages, which you can use for inspiration.

Once you've picked an exercise, follow the instructions in this guide and submit your pull request to the Swift track repository on GitHub.

### Say

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

### List Ops

Implement basic list operations

### Change

Correctly determine change to be given using the least number of coins

### Circular Buffer

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

### Collatz Conjecture

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

### Bank Account

Simulate a bank account supporting opening/closing, withdraws, and deposits of money. Watch out for concurrent transactions!

### Diamond

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

### Forth

Implement an evaluator for a very simple subset of Forth

### React

Implement a basic reactive system.

### Alphametics

Write a function to solve alphametics puzzles.

### Connect

Compute the result for a game of Hex / Polygon

### Two Fer

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

### Parallel Letter Frequency

Count the frequency of letters in texts using parallel computation.

### Protein Translation

Translate RNA sequences into proteins.

### Variable Length Quantity

Implement variable length quantity encoding and decoding.

### Book Store

To try and encourage more sales of different books from a popular 5 book series, a bookshop has decided to offer discounts of multiple-book purchases.

### Proverb

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

### Rail Fence Cipher

Implement encoding and decoding for the rail fence cipher.

### Zipper

Creating a zipper for a binary tree.

### Pov

Reparent a graph on a selected node

### Rectangles

Count the rectangles in an ASCII diagram.

### Spiral Matrix

Given the size, return a square matrix of numbers in spiral order.

### Word Search

Create a program to solve a word search puzzle.

### Complex Numbers

Implement complex numbers.

### Diffie Hellman

Diffie-Hellman key exchange.

### Grep

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

### Scale Generator

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

### Two Bucket

Given two buckets of different size, demonstrate how to measure an exact number of liters.

### Error Handling

Implement various kinds of error handling and resource management

### Markdown

Refactor a Markdown parser

### Sgf Parsing

Parsing a Smart Game Format string.

### Dot Dsl

Write a Domain Specific Language similar to the Graphviz dot language

### Go Counting

Count the scored points on a Go board.

### Hangman

Implement the logic of the hangman game using functional reactive programming.

### Ledger

Refactor a ledger printer.

### Lens Person

Use lenses to update nested records (specific to languages with immutable data).

### Tree Building

Refactor a tree building algorithm.

### Paasio

Report network IO statistics