switch to project format

Fixed a bug in the day1 solution where
the list of totals could add the "current
sum" for a given elf to the list each time
a new entry was added e.g. an input like,

100
200
300

could result in a list like,

[300, 200, 100].

Now we reorder the list at each "reset" (empty line).

.formatter.exs

@@ -0,0 +1,4 @@
+# Used by "mix format"
+[
+  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
+]

.gitignore

@@ -0,0 +1,26 @@
+# The directory Mix will write compiled artifacts to.
+/_build/
+
+# If you run "mix test --cover", coverage assets end up here.
+/cover/
+
+# The directory Mix downloads your dependencies sources to.
+/deps/
+
+# Where third-party dependencies like ExDoc output generated docs.
+/doc/
+
+# Ignore .fetch files in case you like to edit your project deps locally.
+/.fetch
+
+# If the VM crashes, it generates a dump, let's ignore it too.
+erl_crash.dump
+
+# Also ignore archive artifacts (built via "mix archive.build").
+*.ez
+
+# Ignore package tarball (built via "mix hex.build").
+aoc-*.tar
+
+# Temporary files, for example, from tests.
+/tmp/

README.md

@@ -0,0 +1,21 @@
+# Aoc
+
+**TODO: Add description**
+
+## Installation
+
+If [available in Hex](https://hex.pm/docs/publish), the package can be installed
+by adding `aoc` to your list of dependencies in `mix.exs`:
+
+```elixir
+def deps do
+  [
+    {:aoc, "~> 0.1.0"}
+  ]
+end
+```
+
+Documentation can be generated with [ExDoc](https://github.com/elixir-lang/ex_doc)
+and published on [HexDocs](https://hexdocs.pm). Once published, the docs can
+be found at <https://hexdocs.pm/aoc>.
+

lib/day1.ex

@@ -1,4 +1,4 @@
-defmodule Exercise1 do
+defmodule Day1 do
   def to_command(s) do
     try do
       {:add, s |> String.trim() |> String.to_integer()}
@@ -26,17 +26,22 @@ defmodule Exercise1 do
   defp apply_add(n, state) do
     {current, total, exit} = state
     new_current = if is_nil(current) do 0 else current end + n
-    new_total = [ new_current | total ] |> 
+    
+    {new_current, total, exit}
+  end
+
+  defp take_top_three(n, list) do
+    [ n | list ] |> 
       Enum.sort(:desc) |>
       Enum.take(3)
-    {new_current, new_total, exit}
   end
 
   defp apply_reset(state) do
     {current, total, exit} = state
+
     case current do
       nil -> {current, total, true}
-      _ -> {nil, total, exit}
+      _ -> {nil, take_top_three(current, total), exit}
     end
   end
 end

main.exs

@@ -1,3 +1 @@
-import AOCRunner
+AOCRunner.run(Day1)
-import Exercise1
-AOCRunner.run(Exercise1)

mix.exs

@@ -0,0 +1,28 @@
+defmodule Aoc.MixProject do
+  use Mix.Project
+
+  def project do
+    [
+      app: :aoc,
+      version: "0.1.0",
+      elixir: "~> 1.15",
+      start_permanent: Mix.env() == :prod,
+      deps: deps()
+    ]
+  end
+
+  # Run "mix help compile.app" to learn about applications.
+  def application do
+    [
+      extra_applications: [:logger]
+    ]
+  end
+
+  # Run "mix help deps" to learn about dependencies.
+  defp deps do
+    [
+      # {:dep_from_hexpm, "~> 0.3.0"},
+      # {:dep_from_git, git: "https://github.com/elixir-lang/my_dep.git", tag: "0.1.0"}
+    ]
+  end
+end

test/aoc_test.exs

@@ -0,0 +1,8 @@
+defmodule AocTest do
+  use ExUnit.Case
+  doctest Aoc
+
+  test "greets the world" do
+    assert Aoc.hello() == :world
+  end
+end

test/test_helper.exs

@@ -0,0 +1 @@
+ExUnit.start()