day 1

Author: drewknab

.editorconfig

@@ -1,3 +1,7 @@
 [*.cr]
 indent_style = space
-indent_size = 2
+indent_size = 2
+
+[*.gleam]
+indent_style = space
+indent_size = 2

.gitignore

@@ -1,26 +1,4 @@
-# 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").
+*.beam
 *.ez
-
-# Ignore package tarball (built via "mix hex.build").
-adventofcode-*.tar
-
-# Temporary files, for example, from tests.
-/tmp/
+/build
+erl_crash.dump

.tool-versions

@@ -0,0 +1 @@
+erlang 27.1.2

README.md

@@ -0,0 +1,10 @@
+# Advent of Code 2024
+
+Code written in Gleam
+
+## Development
+
+```sh
+gleam run   # Run the project
+gleam test  # Run the tests
+```

gleam.toml

@@ -0,0 +1,21 @@
+name = "adventofcode"
+version = "1.0.0"
+
+# Fill out these fields if you intend to generate HTML documentation or publish
+# your project to the Hex package manager.
+#
+# description = ""
+# licences = ["Apache-2.0"]
+# repository = { type = "github", user = "", repo = "" }
+# links = [{ title = "Website", href = "" }]
+#
+# For a full reference of all the available options, you can have a look at
+# https://gleam.run/writing-gleam/gleam-toml/.
+
+[dependencies]
+gleam_stdlib = ">= 0.34.0 and < 2.0.0"
+simplifile = ">= 2.2.0 and < 3.0.0"
+gtempo = ">= 5.0.2 and < 6.0.0"
+
+[dev-dependencies]
+gleeunit = ">= 1.0.0 and < 2.0.0"

manifest.toml

@@ -0,0 +1,16 @@
+# This file was generated by Gleam
+# You typically do not need to edit this file
+
+packages = [
+  { name = "filepath", version = "1.1.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "filepath", source = "hex", outer_checksum = "67A6D15FB39EEB69DD31F8C145BB5A421790581BD6AA14B33D64D5A55DBD6587" },
+  { name = "gleam_stdlib", version = "0.45.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "206FCE1A76974AECFC55AEBCD0217D59EDE4E408C016E2CFCCC8FF51278F186E" },
+  { name = "gleeunit", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "F7A7228925D3EE7D0813C922E062BFD6D7E9310F0BEE585D3A42F3307E3CFD13" },
+  { name = "gtempo", version = "5.0.2", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gtempo", source = "hex", outer_checksum = "E45DC6838FDA4A6BB57A02090738B2266B7AE16D1012CBBB7FA4EC5C741EA83D" },
+  { name = "simplifile", version = "2.2.0", build_tools = ["gleam"], requirements = ["filepath", "gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "0DFABEF7DC7A9E2FF4BB27B108034E60C81BEBFCB7AB816B9E7E18ED4503ACD8" },
+]
+
+[requirements]
+gleam_stdlib = { version = ">= 0.34.0 and < 2.0.0" }
+gleeunit = { version = ">= 1.0.0 and < 2.0.0" }
+gtempo = { version = ">= 5.0.2 and < 6.0.0" }
+simplifile = { version = ">= 2.2.0 and < 3.0.0" }

readme.md

@@ -0,0 +1,14 @@
+import gleam/io
+import historian_hysteria
+import tempo/duration
+
+pub fn main() {
+  timed(historian_hysteria.part_1)
+  timed(historian_hysteria.part_2)
+}
+
+pub fn timed(func) {
+  let start = duration.start_monotonic()
+  func() |> io.debug
+  io.println("This took " <> duration.since(start) <> " to run!")
+}

shard.yml

@@ -0,0 +1,80 @@
+import gleam/dict
+import gleam/int
+import gleam/list
+import gleam/option
+import gleam/string
+import simplifile as file
+
+pub fn part_1() {
+  let assert Ok(input) = file.read("./input/day1.txt")
+
+  input
+  |> setup()
+  |> list_processor()
+}
+
+pub fn part_2() {
+  let assert Ok(input) = file.read("./input/day1.txt")
+
+  input
+  |> setup()
+  |> similarity_scores()
+}
+
+pub fn list_processor(lists) {
+  let #(left, right) = lists
+
+  let left = list.sort(left, by: int.compare)
+  let right = list.sort(right, by: int.compare)
+
+  left
+  |> list.map2(right, fn(x, y) { int.absolute_value(x - y) })
+  |> list.fold(0, int.add)
+  |> int.absolute_value
+}
+
+pub fn similarity_scores(lists) {
+  let #(left, right) = lists
+  let new = dict.new()
+
+  let counts = list.fold(right, new, similarity_fold)
+
+  list.fold(left, 0, fn(acc, x) {
+    let key = int.to_string(x)
+
+    let sim_score = case dict.get(counts, key) {
+      Ok(i) -> x * i
+      Error(Nil) -> 0
+    }
+    acc + sim_score
+  })
+}
+
+fn increment(key) {
+  case key {
+    option.Some(i) -> i + 1
+    option.None -> 1
+  }
+}
+
+fn similarity_fold(acc, x) {
+  let key = int.to_string(x)
+  dict.upsert(acc, key, increment)
+}
+
+fn folder(acc, item) {
+  let #(left_rest, right_rest) = acc
+
+  let assert [left, right] = string.split(item, "   ")
+  let assert Ok(left) = int.parse(left)
+  let assert Ok(right) = int.parse(right)
+
+  #([left, ..left_rest], [right, ..right_rest])
+}
+
+fn setup(input) {
+  input
+  |> string.trim()
+  |> string.split("\n")
+  |> list.fold(#([], []), folder)
+}