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(** Bounded sequence: keep only the [n] greatest elements. *)

module Make (E : Set.OrderedType) : sig
  type t

  (** [create size] create a bounded sequence of at most [size] elements.

      Raise [Invalid_argument] if [size < 0] or [size > Sys.max_array_length].
   *)
  val create : int -> t

  (** [insert e b] adds element [e] to bounded sequence [b] if:
      - [b] is not full (i.e, we have not inserted [size] elements until now); or
      - there is an element [e'] from [b] such that [E.compare e' e < 0]. 

      Worst-case complexity: O(log n) where n is the size of the heap.
   *)
  val insert : E.t -> t -> unit

  (** [get b] returns the contents of [b] as a sorted list in increasing order
     according to [E.compare].

     Worst-case complexity: O(n log n) where n is the size of the heap.
   *)
  val get : t -> E.t list

  (** [peek b] returns [Some e] if [b] is not empty where [e] is the smallest
     element in [b] according to [E.compare], [None] otherwise.

     Worst-case complexity: O(1).
   *)
  val peek : t -> E.t option
end