gleam 2015 day 1HEADmain

3 files changed, 49 insertions, 2 deletions

diff --git a/gleam/aoc2015/.gitignore b/gleam/aoc2015/.gitignore
index 599be4e..34df305 100644
--- a/gleam/aoc2015/.gitignore
+++ b/gleam/aoc2015/.gitignore
@@ -1,4 +1,5 @@
 *.beam
 *.ez
 /build
+/input
 erl_crash.dump
diff --git a/gleam/aoc2015/src/aoc2015.gleam b/gleam/aoc2015/src/aoc2015.gleam
index dae067e..12d05ab 100644
--- a/gleam/aoc2015/src/aoc2015.gleam
+++ b/gleam/aoc2015/src/aoc2015.gleam
@@ -1,5 +1,5 @@
-import gleam/io
+import gladvent
 
 pub fn main() {
-  io.println("Hello from aoc2015!")
+  gladvent.run()
 }
diff --git a/gleam/aoc2015/src/aoc_2015/day_1.gleam b/gleam/aoc2015/src/aoc_2015/day_1.gleam
new file mode 100644
index 0000000..c398f28
--- /dev/null
+++ b/gleam/aoc2015/src/aoc_2015/day_1.gleam
@@ -0,0 +1,46 @@
+import gleam/bool
+import gleam/list
+import gleam/string
+
+type Direction {
+  Up
+  Down
+}
+
+fn parse(input: String) {
+  use ch <- list.map(string.to_graphemes(input))
+  case ch {
+    "(" -> Up
+    ")" -> Down
+    _ -> panic
+  }
+}
+
+fn traverse(directions: List(Direction), starting_at current_floor: Int) -> Int {
+  case directions {
+    [] -> current_floor
+    [Up, ..rest] -> traverse(rest, current_floor + 1)
+    [Down, ..rest] -> traverse(rest, current_floor - 1)
+  }
+}
+
+pub fn pt_1(input: String) {
+  input |> parse |> traverse(starting_at: 0)
+}
+
+fn find_basement(
+  directions: List(Direction),
+  starting_at current_floor: Int,
+  initial_count count: Int,
+) -> Int {
+  use <- bool.guard(current_floor == -1, count)
+  case directions {
+    [] -> panic
+    [Up, ..rest] -> find_basement(rest, current_floor + 1, count + 1)
+    [Down, ..rest] -> find_basement(rest, current_floor - 1, count + 1)
+  }
+}
+
+pub fn pt_2(input: String) {
+  input |> parse |> find_basement(starting_at: 0, initial_count: 0)
+}