proxpero

// Swift 2.1

extension MutableCollectionType where Self.Generator.Element : Comparable {
    
    /// Return a new sorted collection of the elements in `source` 
    /// using [Selection Sort](https://en.wikipedia.org/wiki/Selection_sort).
    ///
    /// Complexity O(n^2).
    @warn_unused_result(mutable_variant="selectionSortInPlace")
    public func selectionSort() -> Self {

proxpero

// Swift 2.1

extension MutableCollectionType where Self.Generator.Element : Comparable {
    
    /// Return a new sorted collection of the elements in `source`
    /// using [Insertion Sort](https://en.wikipedia.org/wiki/Insertion_sort).
    ///
    /// Complexity O(n^2).
    @warn_unused_result(mutable_variant="insertionSortInPlace")
    public func insertionSort() -> Self {

proxpero

// Swift 2.1

extension MutableCollectionType where Self.Generator.Element : Comparable, Self.Index == Int {
    
    /// Return a new sorted collection of the elements in `source`
    /// using [Shell Sort](https://en.wikipedia.org/wiki/Shellsort).
    ///
    /// Complexity O(n^(3/2)).
    @warn_unused_result(mutable_variant="shellSortInPlace")

proxpero

// Swift 2.1

extension Array where Element : Comparable {
    
    private func merge(var left: Array<Element>, var _ right: Array<Element>) -> Array<Element> {
        
        var result: Array<Element> = []
        
        while !left.isEmpty && !right.isEmpty {
            

proxpero

// As described in: http://proxpero.com/2017/02/14/an-implementation-of-md5/

extension Collection where Iterator.Element == UInt8 {

    /// Returns the md5 hash of self.
    public var md5: String {
        return self.md5Digest.lazy.reduce("") {
            var s = String($1, radix: 16)
            if s.characters.count == 1 {
                s = "0" + s

proxpero

Keybase proof

I hereby claim:

• I am proxpero on github.
• I am proxpero (https://keybase.io/proxpero) on keybase.
• I have a public key whose fingerprint is ABAF 07DE 0D7E EA58 7C60 1131 CB36 31B5 E8CA 11C7

To claim this, I am signing this object:

proxpero

// Accompanying blog post: http://127.0.0.1:4000/2017/07/11/encoding-and-decoding-custom-enums-with-associated-values-in-swift-4
// Also: https://gist.github.com/proxpero/189a723fb96bb88fac5bf9e11d6cf9e2
enum Barcode {
    case upc(Int, Int, Int, Int)
    case qrCode(String)
}

extension Barcode: Codable {

    private enum CodingKeys: String, CodingKey {

proxpero

// Part 1

extension String {
    var characterCounts: [Character: Int] {
        return self.reduce(into: [Character: Int]()) { $0[$1, default: 0] += 1 }
    }
}

extension Bool {
    var intValue: Int {

proxpero

// prepare the puzzle input
let input = loadFile(named: "day1") // convenience function in resources
    .split(separator: "\n")
    .compactMap(Int.init) // extension on Int to init? with String.Subsequence

// part 1
let part1 = input.reduce(0, +)

// part 2

proxpero

// See http://proxpero.com/2017/07/11/encoding-and-decoding-custom-enums-with-associated-values-in-swift-4/
enum Barcode {
    case upc(Int, Int, Int, Int)
    case qrCode(String)
}

extension Barcode: Codable {
    init(from decoder: Decoder) throws {
        self = try Barcode.Coding.init(from: decoder).barcode()
    }