1 files changed, 73 insertions, 0 deletions
diff --git a/codingquest2024/src/day7/solution.gleam b/codingquest2024/src/day7/solution.gleam
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+++ b/codingquest2024/src/day7/solution.gleam
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+import gleam/io
+import gleam/string
+import gleam/set.{type Set}
+import gleam/int
+import gleam/regex.{Match}
+import gleam/option.{Some}
+import simplifile
+
+pub opaque type Item {
+  File(name: String, size: Int)
+  Directory(name: String)
+}
+
+pub fn main() {
+  let assert Ok(data) = simplifile.read(from: "./src/day7/data.txt")
+  let lines = string.split(data, "\n")
+
+  mark_for_deletion(lines, 0, "", set.new())
+  |> io.debug()
+}
+
+fn mark_for_deletion(
+  lines: List(String),
+  deleted: Int,
+  current_folder: String,
+  deleted_folders: Set(String),
+) {
+  case lines {
+    [] -> deleted
+    ["Folder: " <> folder, ..rest] ->
+      mark_for_deletion(rest, deleted, folder, deleted_folders)
+    [file, ..rest] -> {
+      case
+        string.contains(file, "temporary")
+        || string.contains(file, "delete")
+        || set.contains(deleted_folders, current_folder)
+      {
+        True ->
+          case string.contains(file, "[FOLDER") {
+            True -> {
+              file
+              |> get_folder_number()
+              |> set.insert(deleted_folders, _)
+              |> mark_for_deletion(rest, deleted, current_folder, _)
+            }
+            False -> {
+              file
+              |> get_file_size()
+              |> int.add(deleted, _)
+              |> mark_for_deletion(rest, _, current_folder, deleted_folders)
+            }
+          }
+        False ->
+          mark_for_deletion(rest, deleted, current_folder, deleted_folders)
+      }
+    }
+  }
+}
+
+fn get_folder_number(file) {
+  let assert Ok(re) = regex.from_string("\\[FOLDER ([0-9]+)\\]")
+
+  let assert [Match(submatches: [Some(n)], ..)] = regex.scan(re, file)
+  n
+}
+
+fn get_file_size(file) {
+  let assert Ok(re) = regex.from_string("- .+ ([0-9]+)$")
+
+  let assert [Match(submatches: [Some(n)], ..)] = regex.scan(re, file)
+  let assert Ok(n) = int.parse(n)
+  n
+}