FizzBuzz

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.8.0", override: true},
  {:youtube, github: "brooklinjazz/youtube"},
  {:hidden_cell, github: "brooklinjazz/hidden_cell"}
])

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FizzBuzz

In the Elixir cell below create a Module FizzBuzz with a function run/1 which takes in a range.

Enumerate through the integers and return a new list where

• integers divisible by 3 are replaced with fizz
• integers divisible by 5 are replaced with buzz
• integers divisible by 3 and 5 are replaced with fizzbuzz
• integers not matching the above stay the same.

For example,

FizzBuzz.run(1..15)
[1, 2, "fizz", 4, "buzz", "fizz", 7, 8, "fizz", "buzz", 11, "fizz", 13, 14, "fizzbuzz"]

Example Solution

  defmodule FizzBuzz do
    def run(range) do
      Enum.map(range, fn int ->
        cond do
          rem(int, 3) == 0 and rem(int, 5) == 0 -> "fizzbuzz"
          rem(int, 3) == 0 -> "fizz"
          rem(int, 5) == 0 -> "buzz"
          true -> int
        end
      end)
    end
  end

  FizzBuzz.run(1..100)

Enter your solution below.

YouTube.new("https://www.youtube.com/watch?v=QPZ0pIK_wsc&ab_channel=TomScott")

defmodule FizzBuzz do
  @doc """
  FizzBuzz.

  ## Examples

    iex> FizzBuzz.run(1..15)
    [1, 2, "fizz", 4, "buzz", "fizz", 7, 8, "fizz", "buzz", 11, "fizz", 13, 14, "fizzbuzz"]

    iex> FizzBuzz.run(10..15)
    ["buzz", 11, "fizz", 13, 14, "fizzbuzz"]
  """
  def run(range) do
  end
end

Mark As Completed

file_name = Path.basename(Regex.replace(~r/#.+/, __ENV__.file, ""), ".livemd")

save_name =
  case Path.basename(__DIR__) do
    "reading" -> "fizzbuzz_reading"
    "exercises" -> "fizzbuzz_exercise"
  end

progress_path = __DIR__ <> "/../progress.json"
existing_progress = File.read!(progress_path) |> Jason.decode!()

default = Map.get(existing_progress, save_name, false)

form =
  Kino.Control.form(
    [
      completed: input = Kino.Input.checkbox("Mark As Completed", default: default)
    ],
    report_changes: true
  )

Task.async(fn ->
  for %{data: %{completed: completed}} <- Kino.Control.stream(form) do
    File.write!(
      progress_path,
      Jason.encode!(Map.put(existing_progress, save_name, completed), pretty: true)
    )
  end
end)

form

Commit Your Progress

Run the following in your command line from the curriculum folder to track and save your progress in a Git commit. Ensure that you do not already have undesired or unrelated changes by running git status or by checking the source control tab in Visual Studio Code.

$ git checkout -b fizzbuzz-exercise
$ git add .
$ git commit -m "finish fizzbuzz exercise"
$ git push origin fizzbuzz-exercise

Create a pull request from your fizzbuzz-exercise branch to your solutions branch. Please do not create a pull request to the DockYard Academy repository as this will spam our PR tracker.

DockYard Academy Students Only:

Notify your teacher by including @BrooklinJazz in your PR description to get feedback. You (or your teacher) may merge your PR into your solutions branch after review.

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