FizzBuzz with Swift

README.md

FizzBuzz with Swift

Given an integer n, return a string array answer (1-indexed) where:

• answer[i] == "FizzBuzz" if i is divisible by 3 and 5.
• answer[i] == "Fizz" if i is divisible by 3.
• answer[i] == "Buzz" if i is divisible by 5.
• answer[i] == i (as a string) if none of the above conditions are true.

Input: n = 15

Output: ["1", "2", "Fizz", "4", "Buzz", "Fizz", "7", "8", "Fizz", "Buzz", "11", "Fizz", "13", "14", "FizzBuzz"]

FizzBuzz.swift

import Foundation

let fizzValue = "Fizz"
let buzzValue = "Buzz"
let fizzBuzzValue = "FizzBuzz"
let emptyValue = ""

enum FizzBuzz: String {
    case fizz = "Fizz"
    case buzz = "Buzz"
    case empty = ""

    var isEmpty: Bool {
        self == .empty
    }
}

enum Solution1 {

    static func fizzBuzz(_ n: Int) -> [String] {
        guard n > 0 else {
            return []
        }

        return (1...n).map { i in
            let fizz = i.isMultiple(of: 3) ? 1 : 0
            let buzz = i.isMultiple(of: 5) ? 1 : 0
            return fizz == 0 && buzz == 0 ? "\(i)" :
            fizz == 1 && buzz == 1 ? fizzBuzzValue :
            fizz == 1 ? fizzValue :
            buzz == 1 ? buzzValue : ""
        }
    }

}

enum Solution2 {

    static func fizzBuzz(_ n: Int) -> [String] {
        guard n > 0 else {
            return []
        }

        return (1...n).map { i in
            let fizz = i.isMultiple(of: 3) ? fizzValue : emptyValue
            let buzz = i.isMultiple(of: 5) ? buzzValue : emptyValue
            return fizz.isEmpty && buzz.isEmpty ? "\(i)" : fizz + buzz
        }
    }

}

enum Solution3 {

    static func fizzBuzz(_ n: Int) -> [String] {
        guard n > 0 else {
            return []
        }

        return (1...n).map { i in
            let fizz: FizzBuzz = i.isMultiple(of: 3) ? .fizz : .empty
            let buzz: FizzBuzz = i.isMultiple(of: 5) ? .buzz : .empty
            return fizz == .empty && buzz == .empty ? "\(i)" : fizz.rawValue + buzz.rawValue
        }
    }

}

enum Solution4 {

    static func fizzBuzz(_ n: Int) -> [String] {
        guard n > 0 else {
            return []
        }

        return (1...n).map { i in
            let fizz: FizzBuzz = i.isMultiple(of: 3) ? .fizz : .empty
            let buzz: FizzBuzz = i.isMultiple(of: 5) ? .buzz : .empty
            return fizz.isEmpty && buzz.isEmpty ? "\(i)" : fizz.rawValue + buzz.rawValue
        }
    }

}

enum Solution5 {

    static func fizzBuzz(_ n: Int) -> [String] {
        guard n > 0 else {
            return []
        }

        return (1...n).lazy.map { i in
            let fizz: FizzBuzz = i.isMultiple(of: 3) ? .fizz : .empty
            let buzz: FizzBuzz = i.isMultiple(of: 5) ? .buzz : .empty
            return fizz.isEmpty && buzz.isEmpty ? "\(i)" : fizz.rawValue + buzz.rawValue
        }
    }

}

FizzBuzzTests.swift

import Testing
@testable import FizzBuzz

struct FizzBuzzTests {

    let iterations = 100_000
    let expected = ["1", "2", "Fizz", "4", "Buzz", "Fizz", "7", "8", "Fizz", "Buzz", "11", "Fizz", "13", "14", "FizzBuzz"]

    @Test func testSolution1() async throws {
        measure(iterations: iterations) {
            let output = Solution1.fizzBuzz(15)
            #expect(output == expected)
        }
    }

    @Test func testSolution2() async throws {
        measure(iterations: iterations) {
            let output = Solution2.fizzBuzz(15)
            #expect(output == expected)
        }
    }

    @Test func testSolution3() async throws {
        measure(iterations: iterations) {
            let output = Solution3.fizzBuzz(15)
            #expect(output == expected)
        }
    }

    @Test func testSolution4() async throws {
        measure(iterations: iterations) {
            let output = Solution3.fizzBuzz(15)
            #expect(output == expected)
        }
    }

    @Test func testSolution5() async throws {
        measure(iterations: iterations) {
            let output = Solution3.fizzBuzz(15)
            #expect(output == expected)
        }
    }

    private func measure(caller: String = #function, iterations: Int = 100, block: @Sendable () -> Void) {
        let start = Date()
        for _ in 0..<iterations {
            block()
        }
        let duration = Date().timeIntervalSince(start)
        let ms = String(format: "Duration: %.6f ms", duration)
        print("\(caller): Duration: \(ms) ms")
    }

}