【发布时间】：2011-04-24 16:44:21
【问题描述】：
我想在 Java 中实现一个 AVL 树，这是我目前所拥有的：
public class AVLNode {
private int size; /** The size of the tree. */
private int height; /** The height of the tree. */
private Object key;/** The key of the current node. */
private Object data;/** The data of the current node. */
private Comparator comp;/** The {@link Comparator} used by the node. */
/* All the nodes pointed by the current node.*/
private AVLNode left,right,parent,succ,pred;
/* Instantiates a new AVL node.
*
* @param key the key of the node
* @param data the data that the node should keep
* @param comp the comparator to be used in the tree
*/
public AVLNode(Object key, Object data, Comparator comp) {
this(key,data,comp,null);
}
/* Instantiates a new AVL node.
*
* @param key the key of the node
* @param data the data that the node should keep
* @param comp the comparator to be used in the tree
* @param parent the parent of the created node
*/
public AVLNode(Object key, Object data, Comparator comp, AVLNode parent) {
this.data = data;
this.key = key;
this.comp = comp;
this.parent = parent;
this.left = null;
this.right = null;
this.succ = null;
this.pred = null;
this.size = 1;
this.height = 0;
}
/* Adds the given data to the tree.
*
* @param key the key
* @param data the data
* @return the root of the tree after insertion and rotations
* @author <b>students</b>
*/
public AVLNode add(Object key,Object data) {
return null;
}
/* Removes a Node which key is equal
* (by {@link Comparator}) to the given argument.
*
* @param key the key
* @return the root after deletion and rotations
* @author <b>students</b>
*/
public AVLNode remove(Object key) {
return null;
}
我需要实现添加和删除功能。这是我到目前为止所拥有的，两者都应该在O(log(n)) 时间运行。两者都应该返回整棵树的根：
/* Adds a new Node into the tree.
* @param key the key of the new node
* @param data the data of the new node
*/
public void add(Object key,Object data){
if (isEmpty()){
this.root = new AVLNode(key,data,comp);
}
else{
root = this.root.add(key,data);
}
}
/**
* Removes a node n from the tree where
* n.key is equal (by {@link Comparator}) to the given key.
*
* @param key the key
*/
public void remove(Object key){
if (isEmpty()){
return;
}
else
root = this.root.remove(key);
}
我需要有关添加和删除功能的帮助。
是否有任何指南来描述添加和删除操作的工作原理？要复制的库或我可以弄清楚 AVL 树如何/为什么工作的东西？
【问题讨论】：
-
为什么要保存大小和高度？您只需要 AVL 树节点内的余额。
-
这就是他们要我做的，这只是项目的一部分，所以我猜它会在以后使用......
-
您应该接受下面的答案或澄清为什么它不适合您。
标签： java data-structures tree avl-tree