(*
Copyright (c) 2013, Simon Cruanes
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*)

(** {1 Leftist Heaps} *)

(** Polymorphic implementation, following Okasaki *)

type 'a t
  (** Heap containing values of type 'a *)

val empty_with : leq:('a -> 'a -> bool) -> 'a t
  (** Empty heap. The function is used to check whether the first element is
      smaller than the second. *)

val empty : 'a t
  (** Empty heap using Pervasives.compare *)

val is_empty : _ t -> bool
  (** Is the heap empty? *)

val merge : 'a t -> 'a t -> 'a t
  (** Merge two heaps (assume they have the same comparison function) *)

val insert : 'a t -> 'a -> 'a t
  (** Insert a value in the heap *)

val find_min : 'a t -> 'a
  (** Find minimal element, or raise Not_found *)

val extract_min : 'a t -> 'a t * 'a
  (** Extract and returns the minimal element, or raise Not_found *)

val iter : 'a t -> ('a -> unit) -> unit
  (** Iterate on elements *)

val size : _ t -> int
  (** Number of elements (linear) *)

val of_seq : 'a t -> 'a Sequence.t -> 'a t

val to_seq : 'a t -> 'a Sequence.t