NetBSD的红黑树实现
原来论坛有字符上限的限制。不得不截断发在1.2.3楼。
程序代码：/* $NetBSD: tree.h,v 1.8 2004/03/28 19:38:30 provos Exp $ */
/* $OpenBSD: tree.h,v 1.7 2002/10/17 21:51:54 art Exp $ */
/* $FreeBSD$ */
/*-
* Copyright 2002 Niels Provos <provos@citi.umich.edu>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef _SYS_TREE_H_
#define _SYS_TREE_H_
#include <sys/cdefs.h>
/*
* This file defines data structures for different types of trees:
* splay trees and red-black trees.
*
* A splay tree is a self-organizing data structure. Every operation
* on the tree causes a splay to happen. The splay moves the requested
* node to the root of the tree and partly rebalances it.
*
* This has the benefit that request locality causes faster lookups as
* the requested nodes move to the top of the tree. On the other hand,
* every lookup causes memory writes.
*
* The Balance Theorem bounds the total access time for m operations
* and n inserts on an initially empty tree as O((m + n)lg n). The
* amortized cost for a sequence of m accesses to a splay tree is O(lg n);
*
* A red-black tree is a binary search tree with the node color as an
* extra attribute. It fulfills a set of conditions:
* - every search path from the root to a leaf consists of the
* same number of black nodes,
* - each red node (except for the root) has a black parent,
* - each leaf node is black.
*
* Every operation on a red-black tree is bounded as O(lg n).
* The maximum height of a red-black tree is 2lg (n+1).
*/
#define SPLAY_HEAD(name, type) \
struct name { \
struct type *sph_root; /* root of the tree */ \
}
#define SPLAY_INITIALIZER(root) \
{ NULL }
#define SPLAY_INIT(root) do { \
(root)->sph_root = NULL; \
} while (/*CONSTCOND*/ 0)
#define SPLAY_ENTRY(type) \
struct { \
struct type *spe_left; /* left element */ \
struct type *spe_right; /* right element */ \
}
#define SPLAY_LEFT(elm, field) (elm)->field.spe_left
#define SPLAY_RIGHT(elm, field) (elm)->field.spe_right
#define SPLAY_ROOT(head) (head)->sph_root
#define SPLAY_EMPTY(head) (SPLAY_ROOT(head) == NULL)
/* SPLAY_ROTATE_{LEFT,RIGHT} expect that tmp hold SPLAY_{RIGHT,LEFT} */
#define SPLAY_ROTATE_RIGHT(head, tmp, field) do { \
SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(tmp, field); \
SPLAY_RIGHT(tmp, field) = (head)->sph_root; \
(head)->sph_root = tmp; \
} while (/*CONSTCOND*/ 0)
#define SPLAY_ROTATE_LEFT(head, tmp, field) do { \
SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(tmp, field); \
SPLAY_LEFT(tmp, field) = (head)->sph_root; \
(head)->sph_root = tmp; \
} while (/*CONSTCOND*/ 0)
#define SPLAY_LINKLEFT(head, tmp, field) do { \
SPLAY_LEFT(tmp, field) = (head)->sph_root; \
tmp = (head)->sph_root; \
(head)->sph_root = SPLAY_LEFT((head)->sph_root, field); \
} while (/*CONSTCOND*/ 0)
#define SPLAY_LINKRIGHT(head, tmp, field) do { \
SPLAY_RIGHT(tmp, field) = (head)->sph_root; \
tmp = (head)->sph_root; \
(head)->sph_root = SPLAY_RIGHT((head)->sph_root, field); \
} while (/*CONSTCOND*/ 0)
#define SPLAY_ASSEMBLE(head, node, left, right, field) do { \
SPLAY_RIGHT(left, field) = SPLAY_LEFT((head)->sph_root, field); \
SPLAY_LEFT(right, field) = SPLAY_RIGHT((head)->sph_root, field);\
SPLAY_LEFT((head)->sph_root, field) = SPLAY_RIGHT(node, field); \
SPLAY_RIGHT((head)->sph_root, field) = SPLAY_LEFT(node, field); \
} while (/*CONSTCOND*/ 0)
/* Generates prototypes and inline functions */
#define SPLAY_PROTOTYPE(name, type, field, cmp) \
void name##_SPLAY(struct name *, struct type *); \
void name##_SPLAY_MINMAX(struct name *, int); \
struct type *name##_SPLAY_INSERT(struct name *, struct type *); \
struct type *name##_SPLAY_REMOVE(struct name *, struct type *); \
\
/* Finds the node with the same key as elm */ \
static __inline struct type * \
name##_SPLAY_FIND(struct name *head, struct type *elm) \
{ \
if (SPLAY_EMPTY(head)) \
return(NULL); \
name##_SPLAY(head, elm); \
if ((cmp)(elm, (head)->sph_root) == 0) \
return (head->sph_root); \
return (NULL); \
} \
\
static __inline struct type * \
name##_SPLAY_NEXT(struct name *head, struct type *elm) \
{ \
name##_SPLAY(head, elm); \
if (SPLAY_RIGHT(elm, field) != NULL) { \
elm = SPLAY_RIGHT(elm, field); \
while (SPLAY_LEFT(elm, field) != NULL) { \
elm = SPLAY_LEFT(elm, field); \
} \
} else \
elm = NULL; \
return (elm); \
} \
\
static __inline struct type * \
name##_SPLAY_MIN_MAX(struct name *head, int val) \
{ \
name##_SPLAY_MINMAX(head, val); \
return (SPLAY_ROOT(head)); \
}[此贴子已经被作者于2017-7-6 23:32编辑过]
