Swift Coding Puzzles #1 – Simple Pig Latin

I’ve been following Ali Spittel‘s #CodingPuzzle challenges. While I’ve read most of them, I haven’t actually done them. But each of them would be a fun little exercise. So, I figured I’d go back and tackle each of them in Swift.

Before I start, a note: There are always multiple ways to tackle coding challenges. This is just my approach to it. If there are better/more optimal ways of doing it, please comment and share your solutions! I’d love to see them. This is as much a way for me to share what I’ve done as it is for me to learn from how others see problems and want to solve them.

That said, here is the first puzzle:

Puzzle #1 – Simple Pig Latin

“Move the first letter of each word to the end of it, then add “ay” to the end of the word. Leave punctuation marks untouched.”

If this was just taking a sentence without punctuation, this would be a lot easier. You could split the array, modify the words, and rebuild the sentence. But keeping punctuation untouched adds a bit of a challenge.

Being me, I also wanted to make sure that this would handle if someone inadvertently misses a space after some punctuation. (No, this likely doesn’t handle apostrophes properly, so contractions will probably not be correct; but I’m no native Pig Latin speaker to know.) So I may have put a little too much thought into this.

First, I wanted to make a function that modifies a word into its proper Pig Latin form.

/// Takes a word and makes it Pig Latinized
func pigLatin(word: String) -> String {
var newWord = word
let startIndex = newWord.startIndex
let firstCharacter = newWord[startIndex]
newWord.append(firstCharacter)
newWord.append("ay")
newWord.remove(at: startIndex)
return newWord
}

With this function, I can now pass in parts of a sentence as needed. With that done, now I just need to get the words to pass in.

I could have split the array based on space, but that wouldn’t necessarily preserve punctuation. So I instead opted to go through the string character-by-character and parsing words that are found.

func simplePigLatin(_ text: String) -> String {
let characterSet = CharacterSet.whitespacesAndNewlines.union(.punctuationCharacters)
var piggyText = ""
var temporaryWord = ""
for (index, character) in text.enumerated() {
let scalar = character.unicodeScalars.first!
if characterSet.contains(scalar) || index == text.count - 1 {
if temporaryWord.count > 0 {
let pigLatinWord = pigLatin(word: temporaryWord)
piggyText.append(pigLatinWord)
temporaryWord = ""
}

// Append any punctuation or white space
if characterSet.contains(scalar) {
piggyText.append(character)
}
} else {
// Append letter to temporary word
temporaryWord.append(character)
}
}

return piggyText
}

I go through each character and, if it’s a letter, I add it to a temporary word. If I hit a non-letter (punctuation or whitespace) or the end of the string, I take that temporary word, modify it for authentic Pig Latin, and append it to the return string.

With all of that, here are some sample outputs:

let word = simplePigLatin("I wish I could speak in Pig Latin; I really do!")
print(word) // Iay ishway Iay ouldcay peaksay niay igPay atinLay; Iay eallyray oday!

let contractions = simplePigLatin("I've got day-to-day issues.")
print(contractions) // Iay'evay otgay ayday-otay-ayday ssuesiay.

let badSpacing = simplePigLatin("I forgot,this is not where commas,go")
print(badSpacing) // Iay orgotfay,histay siay otnay hereway ommascay,ogay

So that’s how you can do Pig Latin in Swift. No, it’s not perfect. There are other cases that aren’t dealt with, such as how to handle words starting with vowels or ‘qu’. But I’m no linguist.