day 17 gleam incomplete

4 files changed, 102 insertions, 24 deletions

diff --git a/aoc2023/gleam.toml b/aoc2023/gleam.toml
index 8e0eb9c..5b60622 100644
--- a/aoc2023/gleam.toml
+++ b/aoc2023/gleam.toml
@@ -16,6 +16,7 @@ simplifile = "~> 1.0"
 gleam_erlang = "~> 0.23"
 gleam_community_maths = "~> 1.0"
 gleam_otp = "~> 0.8"
+pqueue = "~> 2.0"
 
 [dev-dependencies]
 gleeunit = "~> 1.0"
diff --git a/aoc2023/manifest.toml b/aoc2023/manifest.toml
index 2336490..a6f708a 100644
--- a/aoc2023/manifest.toml
+++ b/aoc2023/manifest.toml
@@ -2,18 +2,19 @@
 # You typically do not need to edit this file
 
 packages = [
-  { name = "adglent", version = "1.2.0", build_tools = ["gleam"], requirements = ["gap", "gleam_httpc", "gleam_community_ansi", "glint", "gleam_otp", "gleam_http", "gleam_erlang", "gleam_stdlib", "simplifile", "snag", "tom"], otp_app = "adglent", source = "hex", outer_checksum = "A20D35001061F8AD602E3B92FB3AC0E1E4EEC642AD2AAE0ACEAD3A85F37DA7F0" },
+  { name = "adglent", version = "1.2.0", build_tools = ["gleam"], requirements = ["glint", "gleam_community_ansi", "snag", "gleam_erlang", "gleam_stdlib", "gleam_http", "gleam_otp", "tom", "gap", "simplifile", "gleam_httpc"], otp_app = "adglent", source = "hex", outer_checksum = "A20D35001061F8AD602E3B92FB3AC0E1E4EEC642AD2AAE0ACEAD3A85F37DA7F0" },
   { name = "gap", version = "1.0.1", build_tools = ["gleam"], requirements = ["gleam_stdlib", "gleam_community_ansi"], otp_app = "gap", source = "hex", outer_checksum = "5E369751DB547BFBDA7735878DC04DA31FCA3112193D61D5D7566010C7C8BA98" },
-  { name = "gleam_community_ansi", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_community_colour", "gleam_stdlib"], otp_app = "gleam_community_ansi", source = "hex", outer_checksum = "8B5A9677BC5A2738712BBAF2BA289B1D8195FDF962BBC769569976AD5E9794E1" },
+  { name = "gleam_community_ansi", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_stdlib", "gleam_community_colour"], otp_app = "gleam_community_ansi", source = "hex", outer_checksum = "8B5A9677BC5A2738712BBAF2BA289B1D8195FDF962BBC769569976AD5E9794E1" },
   { name = "gleam_community_colour", version = "1.2.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_community_colour", source = "hex", outer_checksum = "036C206886AFB9F153C552700A7A0B4D2864E3BC96A20C77E5F34A013C051BE3" },
   { name = "gleam_community_maths", version = "1.0.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_community_maths", source = "hex", outer_checksum = "1B9DB313E94A0E4674CA84C5D29F45ECFE211BFB38ABBD8B23737395F47D08B3" },
   { name = "gleam_erlang", version = "0.23.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_erlang", source = "hex", outer_checksum = "C21CFB816C114784E669FFF4BBF433535EEA9960FA2F216209B8691E87156B96" },
   { name = "gleam_http", version = "3.5.2", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleam_http", source = "hex", outer_checksum = "AECDA43AFD523D07A8F09068598A6E271C505278A0CB6F9C7A2E4365EAE8D11E" },
-  { name = "gleam_httpc", version = "2.1.1", build_tools = ["gleam"], requirements = ["gleam_stdlib", "gleam_http"], otp_app = "gleam_httpc", source = "hex", outer_checksum = "06AC1CA52C9BAA66C9D5C0303B2BF34E39AA1546BB96AEE496E4B06D513AB8C7" },
+  { name = "gleam_httpc", version = "2.1.1", build_tools = ["gleam"], requirements = ["gleam_http", "gleam_stdlib"], otp_app = "gleam_httpc", source = "hex", outer_checksum = "06AC1CA52C9BAA66C9D5C0303B2BF34E39AA1546BB96AEE496E4B06D513AB8C7" },
   { name = "gleam_otp", version = "0.8.0", build_tools = ["gleam"], requirements = ["gleam_erlang", "gleam_stdlib"], otp_app = "gleam_otp", source = "hex", outer_checksum = "18EF8242A5E54BA92F717C7222F03B3228AEE00D1F286D4C56C3E8C18AA2588E" },
   { name = "gleam_stdlib", version = "0.33.0", build_tools = ["gleam"], requirements = [], otp_app = "gleam_stdlib", source = "hex", outer_checksum = "539E37A2AA5EBE8E75F4B74755E4CC604BD957C3000AC8D705A2024886A2738B" },
   { name = "gleeunit", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "gleeunit", source = "hex", outer_checksum = "D3682ED8C5F9CAE1C928F2506DE91625588CC752495988CBE0F5653A42A6F334" },
-  { name = "glint", version = "0.13.0", build_tools = ["gleam"], requirements = ["gleam_community_ansi", "gleam_stdlib", "gleam_community_colour", "snag"], otp_app = "glint", source = "hex", outer_checksum = "46E56049CD370D61F720D319D0AB970408C9336EEB918F08B5DCB1DCE9845FA3" },
+  { name = "glint", version = "0.13.0", build_tools = ["gleam"], requirements = ["gleam_community_colour", "gleam_community_ansi", "gleam_stdlib", "snag"], otp_app = "glint", source = "hex", outer_checksum = "46E56049CD370D61F720D319D0AB970408C9336EEB918F08B5DCB1DCE9845FA3" },
+  { name = "pqueue", version = "2.0.7", build_tools = ["rebar3"], requirements = [], otp_app = "pqueue", source = "hex", outer_checksum = "8B0204BB202335890E4E7F9B99A8EC0B84DDB8513EE298EB180EE9B3BCB4C859" },
   { name = "simplifile", version = "1.0.0", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "simplifile", source = "hex", outer_checksum = "0BD6F0E7DA1A7E11D18B8AD48453225CAFCA4C8CFB4513D217B372D2866C501C" },
   { name = "snag", version = "0.2.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "snag", source = "hex", outer_checksum = "8FD70D8FB3728E08AC425283BB509BB0F012BE1AE218424A597CDE001B0EE589" },
   { name = "tom", version = "0.2.1", build_tools = ["gleam"], requirements = ["gleam_stdlib"], otp_app = "tom", source = "hex", outer_checksum = "5C5A9B8586C547F1F39542B1A3BBD9FEE17AFEAB51CE53B32B13D0D46B421249" },
@@ -26,4 +27,5 @@ gleam_erlang = { version = "~> 0.23" }
 gleam_otp = { version = "~> 0.8" }
 gleam_stdlib = { version = "~> 0.32" }
 gleeunit = { version = "~> 1.0" }
+pqueue = { version = "~> 2.0" }
 simplifile = { version = "~> 1.0" }
diff --git a/aoc2023/src/day17/solve.gleam b/aoc2023/src/day17/solve.gleam
index 200565a..7a01c4d 100644
--- a/aoc2023/src/day17/solve.gleam
+++ b/aoc2023/src/day17/solve.gleam
@@ -1,13 +1,13 @@
 import adglent.{First, Second}
+import gleam/bool
+import gleam/dict.{type Dict}
 import gleam/io
-import gleam/string
 import gleam/list
 import gleam/result
+import gleam/string
+import gleam/set.{type Set}
 import utilities/array2d.{type Posn, Posn}
-import gleam/bool
-import gleam/dict
-import gleam/queue.{type Queue}
-import gleam/set
+import utilities/prioqueue.{type PriorityQueue}
 
 type State {
   State(posn: Posn, heatloss: Int, previous: Posn, history: List(Posn))
@@ -22,7 +22,9 @@ fn make_key(s: State) {
 fn same_dir(s: State) {
   case s.history {
     [] -> []
-    [first, ..] as deltas -> list.take_while(deltas, fn(d) { d == first })
+    [first, ..] as deltas ->
+      list.take_while(deltas, fn(d) { d == first })
+      |> list.take(10)
   }
 }
 
@@ -62,21 +64,32 @@ fn make_state(d: Posn, s: State, grid) {
   )
 }
 
-fn find_path(grid, goal, seen, queue: Queue(State), neighbor_fn, goal_fn) {
-  let assert Ok(#(s, rest)) = queue.pop_front(queue)
-  let key = make_key(s)
-
+fn find_path(
+  grid: Dict(Posn, Int),
+  queue: PriorityQueue(State),
+  seen: Set(#(Posn, List(Posn))),
+  get_neighbors: fn(State) -> List(State),
+  is_goal: fn(State) -> Bool,
+) {
+  let assert Ok(#(state, rest)) = prioqueue.pop(queue)
+  let key =
+    make_key(
+      state
+      |> io.debug,
+    )
   case set.contains(seen, key) {
-    True -> find_path(grid, goal, seen, rest, neighbor_fn, goal_fn)
+    True -> find_path(grid, rest, seen, get_neighbors, is_goal)
     False -> {
-      let seen = set.insert(seen, key)
-      let neighbors: List(State) = neighbor_fn(s)
-
-      case list.find(neighbors, goal_fn) {
+      let now_seen = set.insert(seen, key)
+      let neighbors = get_neighbors(state)
+      case list.find(neighbors, is_goal) {
         Ok(final) -> final.heatloss
-        Error(Nil) -> {
-          let queue = list.fold(neighbors, queue, queue.push_back)
-          find_path(grid, goal, seen, queue, neighbor_fn, goal_fn)
+        _err -> {
+          let now_queue =
+            list.fold(neighbors, rest, fn(acc, n) {
+              prioqueue.insert(acc, n, n.heatloss)
+            })
+          find_path(grid, now_queue, now_seen, get_neighbors, is_goal)
         }
       }
     }
@@ -96,13 +109,13 @@ pub fn part1(input: String) {
     |> list.first
     |> result.map(list.length)
 
+  let start = State(Posn(0, 0), 0, Posn(0, 0), [])
   let goal = Posn(rmax, cmax)
 
   find_path(
     grid,
-    goal,
+    prioqueue.insert(prioqueue.new(), start, 0),
     set.new(),
-    queue.from_list([State(Posn(0, 0), 0, Posn(0, 0), [])]),
     find_good_neighbors(0, 3, _, grid),
     is_goal(_, 1, goal),
   )
diff --git a/aoc2023/src/utilities/prioqueue.gleam b/aoc2023/src/utilities/prioqueue.gleam
new file mode 100644
index 0000000..640748b
--- /dev/null
+++ b/aoc2023/src/utilities/prioqueue.gleam
@@ -0,0 +1,62 @@
+//adapted from https://github.com/byronanderson/adventofcode2021/blob/main/gleam_advent/src/priority_queue.gleam
+
+import gleam/dict.{type Dict}
+
+type Ref
+
+@external(erlang, "erlang", "make_ref")
+fn make_ref() -> Ref
+
+type PQueue(a)
+
+pub opaque type PriorityQueue(a) {
+  PriorityQueue(queue: PQueue(#(a, Ref)), refs: Dict(a, Ref))
+}
+
+type OutResult(a) {
+  Empty
+  Value(a, Int)
+}
+
+@external(erlang, "pqueue2", "new")
+fn new_() -> PQueue(a)
+
+@external(erlang, "pqueue2", "in")
+fn insert_(item: a, prio: Int, queue: PQueue(a)) -> PQueue(a)
+
+@external(erlang, "pqueue2", "pout")
+fn pop_(queue: PQueue(a)) -> #(OutResult(a), PQueue(a))
+
+pub fn new() -> PriorityQueue(a) {
+  PriorityQueue(queue: new_(), refs: dict.new())
+}
+
+pub fn insert(
+  queue: PriorityQueue(a),
+  value: a,
+  priority: Int,
+) -> PriorityQueue(a) {
+  let ref = make_ref()
+
+  let refs =
+    queue.refs
+    |> dict.insert(value, ref)
+
+  PriorityQueue(refs: refs, queue: insert_(#(value, ref), priority, queue.queue),
+  )
+}
+
+pub fn pop(queue: PriorityQueue(a)) -> Result(#(a, PriorityQueue(a)), Nil) {
+  case pop_(queue.queue) {
+    #(Value(#(value, ref), _priority), pqueue) -> {
+      let assert Ok(recently_enqueued_ref) = dict.get(queue.refs, value)
+      case recently_enqueued_ref == ref {
+        True -> Ok(#(value, PriorityQueue(refs: queue.refs, queue: pqueue)))
+        False -> pop(PriorityQueue(refs: queue.refs, queue: pqueue))
+      }
+    }
+    #(Empty, _pqueue) -> {
+      Error(Nil)
+    }
+  }
+}