1/* Et-forest data structure implementation.
2 Copyright (C) 2002-2017 Free Software Foundation, Inc.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; see the file COPYING3. If not see
16 <http://www.gnu.org/licenses/>. */
17
18/* This package implements ET forest data structure. Each tree in
19 the structure maintains a tree structure and offers logarithmic time
20 for tree operations (insertion and removal of nodes and edges) and
21 poly-logarithmic time for nearest common ancestor.
22
23 ET tree stores its structure as a sequence of symbols obtained
24 by dfs(root)
25
26 dfs (node)
27 {
28 s = node;
29 for each child c of node do
30 s = concat (s, c, node);
31 return s;
32 }
33
34 For example for tree
35
36 1
37 / | \
38 2 3 4
39 / |
40 4 5
41
42 the sequence is 1 2 4 2 5 3 1 3 1 4 1.
43
44 The sequence is stored in a slightly modified splay tree.
45 In order to support various types of node values, a hashtable
46 is used to convert node values to the internal representation. */
47
48#ifndef _ET_TREE_H
49#define _ET_TREE_H
50
51#ifdef __cplusplus
52extern "C" {
53#endif /* __cplusplus */
54
55/* The node representing the node in an et tree. */
56struct et_node
57{
58 void *data; /* The data represented by the node. */
59
60 int dfs_num_in, dfs_num_out; /* Number of the node in the dfs ordering. */
61
62 struct et_node *father; /* Father of the node. */
63 struct et_node *son; /* The first of the sons of the node. */
64 struct et_node *left;
65 struct et_node *right; /* The brothers of the node. */
66
67 struct et_occ *rightmost_occ; /* The rightmost occurrence. */
68 struct et_occ *parent_occ; /* The occurrence of the parent node. */
69};
70
71struct et_node *et_new_tree (void *data);
72void et_free_tree (struct et_node *);
73void et_free_tree_force (struct et_node *);
74void et_free_pools (void);
75void et_set_father (struct et_node *, struct et_node *);
76void et_split (struct et_node *);
77struct et_node *et_nca (struct et_node *, struct et_node *);
78bool et_below (struct et_node *, struct et_node *);
79struct et_node *et_root (struct et_node *);
80
81#ifdef __cplusplus
82}
83#endif /* __cplusplus */
84
85#endif /* _ET_TREE_H */
86