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-rw-r--r--aoc2023/src/utilities/prioqueue.gleam64
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diff --git a/aoc2023/src/utilities/prioqueue.gleam b/aoc2023/src/utilities/prioqueue.gleam
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--- a/aoc2023/src/utilities/prioqueue.gleam
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@@ -1,64 +0,0 @@
-//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)
- }
- }
-}