day 8 complete

2 files changed, 20 insertions, 19 deletions

diff --git a/aoc2023/src/day8/solve.gleam b/aoc2023/src/day8/solve.gleam
index dee24a4..cbd2f6a 100644
--- a/aoc2023/src/day8/solve.gleam
+++ b/aoc2023/src/day8/solve.gleam
@@ -2,7 +2,7 @@ import adglent.{First, Second}
 import gleam/bool
 import gleam/dict.{type Dict}
 import gleam/io
-import gleam/iterator.{Next}
+import gleam/iterator.{type Iterator, Next}
 import gleam/list
 import gleam/option.{Some}
 import gleam/string
@@ -16,7 +16,7 @@ type Paths {
 type Maze =
   Dict(String, Paths)
 
-fn parse(input: String) {
+fn parse(input: String) -> #(Iterator(String), Dict(String, Paths)) {
   let [directions_str, maze_str] = string.split(input, "\n\n")
 
   let directions =
@@ -39,7 +39,13 @@ fn parse(input: String) {
   #(directions, maze)
 }
 
-fn to_next_step(current, stop_at, count, directions, maze: Maze) {
+fn to_next_step(
+  current: String,
+  stop_at: String,
+  count: Int,
+  directions: Iterator(String),
+  maze: Maze,
+) -> Int {
   use <- bool.guard(string.ends_with(current, stop_at), count)
   let assert Next(next_direction, rest_directions) = iterator.step(directions)
   let assert Ok(paths) = dict.get(maze, current)
@@ -50,27 +56,22 @@ fn to_next_step(current, stop_at, count, directions, maze: Maze) {
   |> to_next_step(stop_at, count + 1, rest_directions, maze)
 }
 
-pub fn part1(input: String) {
+pub fn part1(input: String) -> Int {
   let #(directions, maze) = parse(input)
 
   to_next_step("AAA", "ZZZ", 0, directions, maze)
-  |> string.inspect
 }
 
-pub fn part2(input: String) {
+pub fn part2(input: String) -> Int {
   let #(directions, maze) = parse(input)
 
-  maze
-  |> dict.keys
-  |> list.filter(string.ends_with(_, "A"))
-  |> list.fold(
-    1,
-    fn(acc, name) {
+  use acc, name <- list.fold(dict.keys(maze), 1)
+  case string.ends_with(name, "A") {
+    False -> acc
+    True ->
       to_next_step(name, "Z", 0, directions, maze)
       |> arithmetics.lcm(acc)
-    },
-  )
-  |> string.inspect
+  }
 }
 
 pub fn main() {
diff --git a/aoc2023/test/day8/day8_test.gleam b/aoc2023/test/day8/day8_test.gleam
index e54d887..2cd499a 100644
--- a/aoc2023/test/day8/day8_test.gleam
+++ b/aoc2023/test/day8/day8_test.gleam
@@ -4,10 +4,10 @@ import adglent.{type Example, Example}
 import day8/solve
 
 type Problem1AnswerType =
-  String
+  Int
 
 type Problem2AnswerType =
-  String
+  Int
 
 /// Add examples for part 1 here:
 /// ```gleam
@@ -20,7 +20,7 @@ const part1_examples: List(Example(Problem1AnswerType)) = [
 AAA = (BBB, BBB)
 BBB = (AAA, ZZZ)
 ZZZ = (ZZZ, ZZZ)",
-    "6",
+    6,
   ),
 ]
 
@@ -40,7 +40,7 @@ const part2_examples: List(Example(Problem2AnswerType)) = [
 22C = (22Z, 22Z)
 22Z = (22B, 22B)
 XXX = (XXX, XXX)",
-    "6",
+    6,
   ),
 ]