Source file `map_.ml`

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
(*pad: same than for Setb,  module Make(Ord: OrderedType) = struct *)

(***********************************************************************)
(*                                                                     *)
(*                           Objective Caml                            *)
(*                                                                     *)
(*            Xavier Leroy, projet Cristal, INRIA Rocquencourt         *)
(*                                                                     *)
(*  Copyright 1996 Institut National de Recherche en Informatique et   *)
(*  en Automatique.  All rights reserved.  This file is distributed    *)
(*  under the terms of the GNU Library General Public License, with    *)
(*  the special exception on linking described in file ../LICENSE.     *)
(*                                                                     *)
(***********************************************************************)

(* map.ml 1.15 2004/04/23 10:01:33 xleroy Exp  *)

(*
    type key = Ord.t

    type 'a t =
        Empty
      | Node of 'a t * key * 'a * 'a t * int
*)
  type ('key, 'v) t = 
      Empty
    | Node of ('key, 'v) t * 'key * 'v * ('key, 'v) t * int

    let empty = Empty

    let is_empty = function Empty -> true | _ -> false

    let height = function
        Empty -> 0
      | Node(_,_,_,_,h) -> h

    let create l x d r =
      let hl = height l and hr = height r in
      Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))

    let bal l x d r =
      let hl = match l with Empty -> 0 | Node(_,_,_,_,h) -> h in
      let hr = match r with Empty -> 0 | Node(_,_,_,_,h) -> h in
      if hl > hr + 2 then begin
        match l with
          Empty -> invalid_arg "Map.bal"
        | Node(ll, lv, ld, lr, _) ->
            if height ll >= height lr then
              create ll lv ld (create lr x d r)
            else begin
              match lr with
                Empty -> invalid_arg "Map.bal"
              | Node(lrl, lrv, lrd, lrr, _)->
                  create (create ll lv ld lrl) lrv lrd (create lrr x d r)
            end
      end else if hr > hl + 2 then begin
        match r with
          Empty -> invalid_arg "Map.bal"
        | Node(rl, rv, rd, rr, _) ->
            if height rr >= height rl then
              create (create l x d rl) rv rd rr
            else begin
              match rl with
                Empty -> invalid_arg "Map.bal"
              | Node(rll, rlv, rld, rlr, _) ->
                  create (create l x d rll) rlv rld (create rlr rv rd rr)
            end
      end else
        Node(l, x, d, r, (if hl >= hr then hl + 1 else hr + 1))

    let rec add x data = function
        Empty ->
          Node(Empty, x, data, Empty, 1)
      | Node(l, v, d, r, h) ->
          let c = compare x v in
          if c = 0 then
            Node(l, x, data, r, h)
          else if c < 0 then
            bal (add x data l) v d r
          else
            bal l v d (add x data r)

    let rec find x = function
        Empty ->
          raise Not_found
      | Node(l, v, d, r, _) ->
          let c = compare x v in
          if c = 0 then d
          else find x (if c < 0 then l else r)

    let rec mem x = function
        Empty ->
          false
      | Node(l, v, d, r, _) ->
          let c = compare x v in
          c = 0 || mem x (if c < 0 then l else r)

    let rec min_binding = function
        Empty -> raise Not_found
      | Node(Empty, x, d, r, _) -> (x, d)
      | Node(l, x, d, r, _) -> min_binding l

    let rec remove_min_binding = function
        Empty -> invalid_arg "Map.remove_min_elt"
      | Node(Empty, x, d, r, _) -> r
      | Node(l, x, d, r, _) -> bal (remove_min_binding l) x d r

    let merge t1 t2 =
      match (t1, t2) with
        (Empty, t) -> t
      | (t, Empty) -> t
      | (_, _) ->
          let (x, d) = min_binding t2 in
          bal t1 x d (remove_min_binding t2)

    let rec remove x = function
        Empty ->
          Empty
      | Node(l, v, d, r, h) ->
          let c = compare x v in
          if c = 0 then
            merge l r
          else if c < 0 then
            bal (remove x l) v d r
          else
            bal l v d (remove x r)

    let rec iter f = function
        Empty -> ()
      | Node(l, v, d, r, _) ->
          iter f l; f v d; iter f r

    let rec map f = function
        Empty               -> Empty
      | Node(l, v, d, r, h) -> Node(map f l, v, f d, map f r, h)

    let rec mapi f = function
        Empty               -> Empty
      | Node(l, v, d, r, h) -> Node(mapi f l, v, f v d, mapi f r, h)

    let rec fold f m accu =
      match m with
        Empty -> accu
      | Node(l, v, d, r, _) ->
          fold f l (f v d (fold f r accu))

(* addons pad *)
let of_list xs =
  List.fold_left (fun acc (k, v) -> add k v acc) empty xs

let to_list t =
  fold (fun k v acc -> (k,v)::acc) t []