62,621
社区成员
发帖
与我相关
我的任务
分享给你一个代码(二叉搜索树)比较简单可以自己改改
package test;
/**
* 节点
* @author Administrator
*/
public class Node {
int i;
Node leftNode;
Node rightNode;
}
-------------------------〉〉〉〉〉
package test;
import java.util.Random;
/**
* 二叉搜索树
* @author Administrator
*
*/
public class Tree {
Node root;//根节点
/**
* 查找节点
* @param key 查找的关键字
* @return 关键字所在节点
*/
public Node find(int key){
Node currentNode = root;
while(currentNode.i != key){
if(key > currentNode.i){
currentNode = currentNode.rightNode;
}else{
currentNode = currentNode.leftNode;
}
if(null == currentNode){
return null;
}
}
return currentNode;
}
/**
* 查找最大的节点
* @return 最大的节点
*/
public Node findMax(){
Node currentNode = root;
while(null != currentNode.rightNode){
currentNode = currentNode.rightNode;
}
return currentNode;
}
/**
* 查找最小的节点
* @return 最小的节点
*/
public Node findMin(){
Node currentNode = root;
while(null != currentNode.leftNode){
currentNode = currentNode.leftNode;
}
return currentNode;
}
/**
* 遍历树
* @param node
*/
public void traverse(Node node){
if(null != node){
traverse(node.leftNode);
System.out.println(node.i);
traverse(node.rightNode);
}
}
/**
* 插入节点
* @param node 需要插入的节点
*/
public void insert(Node node){
if(null == root){
root = node;
}else{
Node currentNode = root;
while(true){
if(currentNode.i > node.i){
if(null == currentNode.leftNode){
currentNode.leftNode = node;
return;
}else{
currentNode = currentNode.leftNode;
}
}else{
if(null == currentNode.rightNode){
currentNode.rightNode = node;
return;
}else{
currentNode = currentNode.rightNode;
}
}
}
}
}
/**
* 获得父节点
* @param node 原节点
* @return 原节点的父节点
*/
public Node getParentNode(Node node){
Node parentNode = root;
System.out.println("parentNode:"+parentNode.i);
while(true){
if(parentNode.leftNode.equals(node) || parentNode.rightNode.equals(node)){
return parentNode;
}else if(parentNode.leftNode.i > node.i){
parentNode = parentNode.leftNode;
}else{
parentNode = parentNode.rightNode;
}
}
}
/**
* 获得后继节点
* @param node 原节点
* @return 原节点的后继节点
*/
public Node getSuccessorNode(Node node){
Node SuccessorNode = node.rightNode;
while(SuccessorNode.leftNode != null){
SuccessorNode = SuccessorNode.leftNode;
}
return SuccessorNode;
}
/**
* 删除节点
* @param deleteNode 要删除的节点
*/
public void deleteNode(Node deleteNode){
if(deleteNode.equals(root)){
root = null;
}else{
Node leftNode = deleteNode.leftNode;
Node rightNode = deleteNode.rightNode;
Node parentNode = getParentNode(deleteNode);
if(parentNode.leftNode == deleteNode){
if(null == leftNode && null == rightNode){
parentNode.leftNode = null;
}else if(null != leftNode && null != rightNode){
Node successorNode = getSuccessorNode(deleteNode);
getParentNode(successorNode).leftNode = successorNode.rightNode;
parentNode.leftNode = successorNode;
successorNode.leftNode = leftNode;
successorNode.rightNode = rightNode;
}else{
parentNode.leftNode = null==leftNode?rightNode:leftNode;
}
}else{
if(null == leftNode && null == rightNode){
parentNode.rightNode = null;
}else if(null != leftNode && null != rightNode){
Node successorNode = getSuccessorNode(deleteNode);
getParentNode(successorNode).leftNode = successorNode.rightNode;
parentNode.leftNode = successorNode;
successorNode.leftNode = leftNode;
successorNode.rightNode = rightNode;
}else{
parentNode.rightNode = null==leftNode?rightNode:leftNode;
}
}
}
}
/**
* 按关键字删除节点
* @param key 要删除节点的关键字
*/
public void deleteNode(int key){
deleteNode(find(key));
}
public static void main(String[] args){
Tree tree = new Tree();
Random r = new Random();
for(int i = 0; i < 50; i++){
Node node = new Node();
node.i = r.nextInt(100);
tree.insert(node);
}
tree.traverse(tree.root);
tree.deleteNode(50);
System.out.println("max:"+tree.findMax().i);
tree.traverse(tree.root);
System.out.println("min:"+tree.findMin().i);
}
}