高度平衡树 -- AVL 树
Scheme 的表达, 优雅.
#lang scheme
( define nil '() )
( define ( root tree )( car tree ) )
( define ( left-tree tree )( cadr tree ) )
( define ( right-tree tree )( caddr tree ) )
( define ( height tree )
( cond [ ( null? tree ) 0 ]
[ else ( cadddr tree ) ] ) )
( define ( make-leaf elem )( list elem nil nil 1 ) )
( define ( make-avl-tree root left right )
( list root left right ( + 1 ( max ( height left )
( height right ) ) ) ) )
( define ( contains-elem?
elem tree )
( cond [ ( null? tree ) false ]
[ ( = elem ( root tree ) ) true ]
[ ( < elem ( root tree ) )
( contains-elem?
elem ( left-tree tree ) ) ]
[ ( > elem ( root tree ) )
( contains-elem? elem ( right-tree tree ) ) ] ) )
( define ( rotate-left-left tree )
( cond [ ( null? tree ) tree ]
[ else ( make-avl-tree ( root ( left-tree tree ) )
( left-tree ( left-tree tree ) )
( make-avl-tree ( root tree )
( right-tree ( left-tree tree ) )
( right-tree tree ) ) ) ] ) )
( define ( rotate-right-right tree )
( cond [ ( null? tree ) tree ]
[ else ( make-avl-tree ( root ( right-tree tree ) )
( make-avl-tree ( root tree )
( left-tree tree )
( left-tree ( right-tree tree ) ) )
( right-tree ( right-tree tree ) ) ) ] ) )
( define ( rotate-right-left tree )
( cond [ ( null?
tree ) tree ]
[ else ( make-avl-tree ( left-tree ( right-tree tree ) )
( make-avl-tree ( root tree )
( left-tree tree )
( left-tree ( left-tree ( right-tree tree ) ) ) )
( make-avl-tree ( root ( right-tree tree ) )
( right-tree ( left-tree ( right-tree tree ) ) )
( right-tree ( right-tree tree ) ) ) ) ] ) )
( define ( rotate-left-right tree )
( cond [ ( null?
tree ) tree ]
[ else ( make-avl-tree ( root ( right-tree ( left-tree tree ) ) )
( make-avl-tree ( root ( left-tree tree ) )
( left-tree ( left-tree tree ) )
( left-tree ( right-tree ( left-tree tree ) ) ) )
( make-avl-tree ( root tree )
( right-tree ( right-tree ( left-tree tree ) ) )
( right-tree tree ) ) ) ] ) )
( define ( balance-avl-tree tree )
( define ( factor tree )
( - ( height ( right-tree tree ) )
( height ( left-tree tree ) ) ) )
( let ( [ f ( factor tree ) ] )
( cond [ ( = f 2 )
( cond [ ( < ( factor ( right-tree tree ) ) 0 )
( rotate-right-left tree ) ]
[ else ( rotate-right-right tree ) ] ) ]
[ ( = f -2 )
( cond [ ( > ( factor ( left-tree tree ) ) 0 )
( rotate-left-right tree ) ]
[ else ( rotate-left-left tree ) ] ) ]
[ else tree ] ) ) )
( define ( insert-elem elem tree )
( define ( insert-in-son elem tree )
( cond [ ( null? tree )
( make-leaf elem ) ]
[ ( < elem ( root tree ) )
( let* ( [ newLeftTree ( insert-in-son elem ( left-tree tree ) ) ]
[ newAVLTree ( make-avl-tree ( root tree )
newLeftTree
( right-tree tree ) ) ] )
( balance-avl-tree newAVLTree ) ) ]
[ ( > elem ( root tree ) )
( let* ( [ newRightTree ( insert-in-son elem ( right-tree tree ) ) ]
[ newAVLTree ( make-avl-tree ( root tree )
( left-tree tree )
newRightTree ) ] )
( balance-avl-tree newAVLTree ) ) ]
[ else tree ] ) )
( cond [ ( contains-elem? elem tree ) tree ]
[ else ( insert-in-son elem tree ) ] ) )
( define ( delete-elem elem tree )
( define ( delete-left-most tree )
( cond [ ( left-empty? tree ) tree ]
[ else ( let* ( [ leftMost ( delete-left-most ( left-tree tree ) ) ]
[ newRightTree ( make-avl-tree ( root tree )
( right-tree leftMost )
( right-tree tree ) ) ] )
( make-avl-tree ( root leftMost )
nil
( balance-avl-tree newRightTree ) ) ) ] ) )
( define ( delete-in-son elem tree )
( cond [ ( < elem ( root tree ) )
( let* ( [ newLeftTree ( delete-in-son elem ( left-tree tree ) ) ]
[ newAVLTree ( make-avl-tree ( root tree )
newLeftTree
( right-tree tree ) ) ] )
( balance-avl-tree newAVLTree ) ) ]
[ ( > elem ( root tree ) )
( let* ( [ newRightTree ( delete-in-son elem ( right-tree tree ) ) ]
[ newAVLTree ( make-avl-tree ( root tree )
( left-tree tree )
newRightTree ) ] )
( balance-avl-tree newAVLTree ) ) ]
[ ( = elem ( root tree ) )
( cond [ ( and ( right-empty? tree )
( left-empty? tree ) )
nil ]
[ ( right-empty? tree )
( left-tree tree ) ]
[ ( left-empty? tree )
( right-tree tree ) ]
[ else ( let ( [ leftMost ( delete-left-most ( right-tree tree ) ) ] )
( make-avl-tree ( root leftMost )
( left-tree tree )
( right-tree leftMost ) ) ) ] ) ] ) )
( define ( left-empty? tree )( null?
( left-tree tree ) ) )
( define ( right-empty? tree )( null?
( right-tree tree ) ) )
( cond [ ( contains-elem?
elem tree )
( delete-in-son elem tree ) ]
[ else tree ] ) )
( define ( list->avl elems )
( define ( iter elems tree )
( cond [ ( null?
elems ) tree ]
[ else ( iter ( cdr elems )
( insert-elem ( car elems ) tree ) ) ] ) )
( cond [ ( null? elems ) '() ]
[ else ( let( [ avl ( make-leaf ( car elems ) ) ] )
( iter ( cdr elems ) avl ) ) ] ) )
高度平衡树 -- AVL 树的更多相关文章
- 【数据结构】平衡二叉树—AVL树
(百度百科)在计算机科学中,AVL树是最先发明的自平衡二叉查找树.在AVL树中任何节点的两个子树的高度最大差别为一,所以它也被称为高度平衡树.查找.插入和删除在平均和最坏情况下都是O(log n).增 ...
- AVL树(一)之 图文解析 和 C语言的实现
概要 本章介绍AVL树.和前面介绍"二叉查找树"的流程一样,本章先对AVL树的理论知识进行简单介绍,然后给出C语言的实现.本篇实现的二叉查找树是C语言版的,后面章节再分别给出C++ ...
- AVL树的左旋右旋理解 (转)
AVL树是最先发明的自平衡二叉查找树.在AVL树中任何节点的两个子树的高度最大差别为一,所以它也被称为高度平衡树.查找.插入和删除在平均和最坏情况下都是O(log n).增加和删除可能需要通过一次或多 ...
- 简单数据结构———AVL树
C - 万恶的二叉树 Crawling in process... Crawling failed Time Limit:1000MS Memory Limit:32768KB 64b ...
- 算法二叉搜索树之AVL树
最近学习了二叉搜索树中的AVL树,特在此写一篇博客小结. 1.引言 对于二叉搜索树而言,其插入查找删除等性能直接和树的高度有关,因此我们发明了平衡二叉搜索树.在计算机科学中,AVL树是最先发明的自平衡 ...
- AVL树,红黑树
AVL树 https://baike.baidu.com/item/AVL%E6%A0%91/10986648 在计算机科学中,AVL树是最先发明的自平衡二叉查找树.在AVL树中任何节点的两个子树的高 ...
- AVL树的理解及自写AVL树
AVL树是最先发明的自平衡二叉查找树.在AVL树中任何节点的两个子树的高度最大差别为一,所以它也被称为高度平衡树.查找.插入和删除在平均和最坏情况下都是O(log n).增加和删除可能需要通过一次或多 ...
- 红黑树与AVL树
概述:本文从排序二叉树作为引子,讲解了红黑树,最后把红黑树和AVL树做了一个比较全面的对比. 1 排序二叉树 排序二叉树是一种特殊结构的二叉树,可以非常方便地对树中所有节点进行排序和检索. 排序二叉树 ...
- AVL树的实现——c++
一.概念 AVL树是根据它的发明者G.M. Adelson-Velsky和E.M. Landis命名的.它是最先发明的自平衡二叉查找树,也被称为高度平衡树.相比于"二叉查找树",它 ...
随机推荐
- 【bzoj2839】【集合计数】容斥原理+线性求阶乘逆元小技巧
(上不了p站我要死了,侵权度娘背锅) Description 一个有N个元素的集合有2^N个不同子集(包含空集),现在要在这2^N个集合中取出若干集合(至少一个),使得 它们的交集的元素个数为K,求取 ...
- Jenkins的安装方法(Windows/Linux)
前提:要确定本机全部安装了JDK 一.先说官方的安装方式 打开网址:https://wiki.jenkins-ci.org/display/JENKINS/Installing+Jenkins,会留意 ...
- C#的多线程——使用async和await来完成异步编程(Asynchronous Programming with async and await)
https://msdn.microsoft.com/zh-cn/library/mt674882.aspx 侵删 更新于:2015年6月20日 欲获得最新的Visual Studio 2017 RC ...
- centos查找文件
centos查找文件 [root@localhost ~]# find / -name libmysqlclient.so
- 【power designer】使用power designer编辑pdm物理模型图时,为字段添加中文备注
如下图: 1.双击下图修改 应用如下 2.为数据列添加备注属性 然后为备注列添加 中文备注 [注意,这里有个小技巧,如果光标已经点进去这个单元格,是不能复制进去文字的,但是第一次点击单元格,是可以复制 ...
- SuperMap iClient如何使用WMTS地图服务(转)
http://blog.sina.com.cn/s/blog_6259ebd50102v221.html 什么是WMTS服务 WMTS,切片地图Web服务(Web Map Tile Service)当 ...
- ElasticSearch 安装中文分词器
1.安装中文分词器IK 下载地址:https://github.com/medcl/elasticsearch-analysis-ik 在线下载安装: elasticsearch-plugin.bat ...
- Spark-Join优化之Broadcast
适用场景 进行join中至少有一个RDD的数据量比较少(比如几百M,或者1-2G) 因为,每个Executor的内存中,都会驻留一份广播变量的全量数据 Broadcast与map进行join代码示例 ...
- 【Hadoop】Hadoop HA 部署 详细过程(架构、机器规划、配置文件、部署步骤)
1.概念.架构 2.配置文件示例.部署步骤 hadoop2.0已经发布了稳定版本了,增加了很多特性,比如HDFS HA.YARN等.最新的hadoop-2.4.1又增加了YARN HA 注意:apac ...
- ElastcSearch的Mapping映射建立
根据oracle的字段来建立ElasticSearch的Mapping public class Start { private static Logger log = LoggerFactory.g ...