1 /* glpavl.h (binary search tree) */
2 
3 /***********************************************************************
4 *  This code is part of GLPK (GNU Linear Programming Kit).
5 *
6 *  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
7 *  2009, 2010 Andrew Makhorin, Department for Applied Informatics,
8 *  Moscow Aviation Institute, Moscow, Russia. All rights reserved.
9 *  E-mail: <mao@gnu.org>.
10 *
11 *  GLPK is free software: you can redistribute it and/or modify it
12 *  under the terms of the GNU General Public License as published by
13 *  the Free Software Foundation, either version 3 of the License, or
14 *  (at your option) any later version.
15 *
16 *  GLPK is distributed in the hope that it will be useful, but WITHOUT
17 *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
18 *  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
19 *  License for more details.
20 *
21 *  You should have received a copy of the GNU General Public License
22 *  along with GLPK. If not, see <http://www.gnu.org/licenses/>.
23 ***********************************************************************/
24 
25 #ifndef GLPAVL_H
26 #define GLPAVL_H
27 
28 #include "glpdmp.h"
29 
30 typedef struct AVL AVL;
31 typedef struct AVLNODE AVLNODE;
32 
33 struct AVL
34 {     /* AVL tree (Adelson-Velsky & Landis binary search tree) */
35       DMP *pool;
36       /* memory pool for allocating nodes */
37       AVLNODE *root;
38       /* pointer to the root node */
39       int (*fcmp)(void *info, const void *key1, const void *key2);
40       /* application-defined key comparison routine */
41       void *info;
42       /* transit pointer passed to the routine fcmp */
43       int size;
44       /* the tree size (the total number of nodes) */
45       int height;
46       /* the tree height */
47 };
48 
49 struct AVLNODE
50 {     /* node of AVL tree */
51       const void *key;
52       /* pointer to the node key (data structure for representing keys
53          is supplied by the application) */
54       int rank;
55       /* node rank = relative position of the node in its own subtree =
56          the number of nodes in the left subtree plus one */
57       int type;
58       /* reserved for the application specific information */
59       void *link;
60       /* reserved for the application specific information */
61       AVLNODE *up;
62       /* pointer to the parent node */
63       short int flag;
64       /* node flag:
65          0 - this node is the left child of its parent (or this node is
66              the root of the tree and has no parent)
67          1 - this node is the right child of its parent */
68       short int bal;
69       /* node balance = the difference between heights of the right and
70          left subtrees:
71          -1 - the left subtree is higher than the right one;
72           0 - the left and right subtrees have the same height;
73          +1 - the left subtree is lower than the right one */
74       AVLNODE *left;
75       /* pointer to the root of the left subtree */
76       AVLNODE *right;
77       /* pointer to the root of the right subtree */
78 };
79 
80 #define avl_create_tree _glp_avl_create_tree
81 AVL *avl_create_tree(int (*fcmp)(void *info, const void *key1,
82       const void *key2), void *info);
83 /* create AVL tree */
84 
85 #define avl_strcmp _glp_avl_strcmp
86 int avl_strcmp(void *info, const void *key1, const void *key2);
87 /* compare character string keys */
88 
89 #define avl_insert_node _glp_avl_insert_node
90 AVLNODE *avl_insert_node(AVL *tree, const void *key);
91 /* insert new node into AVL tree */
92 
93 #define avl_set_node_type _glp_avl_set_node_type
94 void avl_set_node_type(AVLNODE *node, int type);
95 /* assign the type field of specified node */
96 
97 #define avl_set_node_link _glp_avl_set_node_link
98 void avl_set_node_link(AVLNODE *node, void *link);
99 /* assign the link field of specified node */
100 
101 #define avl_find_node _glp_avl_find_node
102 AVLNODE *avl_find_node(AVL *tree, const void *key);
103 /* find node in AVL tree */
104 
105 #define avl_get_node_type _glp_avl_get_node_type
106 int avl_get_node_type(AVLNODE *node);
107 /* retrieve the type field of specified node */
108 
109 #define avl_get_node_link _glp_avl_get_node_link
110 void *avl_get_node_link(AVLNODE *node);
111 /* retrieve the link field of specified node */
112 
113 #define avl_delete_node _glp_avl_delete_node
114 void avl_delete_node(AVL *tree, AVLNODE *node);
115 /* delete specified node from AVL tree */
116 
117 #define avl_delete_tree _glp_avl_delete_tree
118 void avl_delete_tree(AVL *tree);
119 /* delete AVL tree */
120 
121 #endif
122 
123 /* eof */
124