相关疑难解决方法(0)

我正在自学俄冈崎的纯功能数据结构,现在正在练习3.4,它要求推理并实施一个重量偏向的左派堆.这是我的基本实现:

(* 3.4 (b) *)
functor WeightBiasedLeftistHeap (Element : Ordered) : Heap =
struct
  structure Elem = Element

  datatype Heap = E | T of int * Elem.T * Heap * Heap

  fun size E = 0
    | size (T (s, _, _, _)) = s
  fun makeT (x, a, b) =
    let
      val sizet = size a + size b + 1
    in
      if size a >= size b then T (sizet, x, a, b)
      else T …