Java--算法--树结构

  1. 数的基本介绍:
  2. 二叉树的基本介绍:
    1.  

       

  3. 二叉树的遍历:

    1.  

       

    2. package com.model.tree;
      
      /**
       * @Description:测试类
       * @Author: 张紫韩
       * @Crete 2021/7/13 18:54
       * 演示二叉树的遍历
       */
      public class TreeDemo01 {
          public static void main(String[] args) {
      
              Node root = new Node(1, "张紫韩");
              Node node2 = new Node(2, "张紫韩2");
              Node node3 = new Node(3, "张紫韩3");
              Node node4 = new Node(4, "张紫韩4");
              root.setLeft(node2);
              root.setRight(node3);
              root.getRight().setRight(node4);
              BinaryTree tree = new BinaryTree(root);
              tree.perOrder();
              tree.infixOrder();
              tree.postOrder();
      //        System.out.println(tree.preFind(node2));
      
          }
      }
      
      class BinaryTree {
          public Node root;
      
          public BinaryTree(Node root) {
              this.root = root;
          }
      
          //   遍历这个树
          public void perOrder(){
              if (root!=null){
                  root.preOrder();
              }else {
                  System.out.println("当前的树为空");
              }
          }
          public void infixOrder(){
              if (root!=null){
                  root.infixOrder();
              }else {
                  System.out.println("当前的树为空");
              }
          }
          public void postOrder(){
              if (root!=null){
                  root.postOrder();
              }else {
                  System.out.println("当前的树为空");
              }
          }
      
          public Node preFind(Node node){
              return root.preFind(node);
          }
      
      }
      
      class Node {
          private int id;
          private String name;
          private Node left;
          private Node right;
      
          @Override
          public String toString() {
              return "Node{" +
                      "id=" + id +
                      ", name='" + name + '\'' +
                      '}';
          }
      
          public int getId() {
              return id;
          }
      
          public void setId(int id) {
              this.id = id;
          }
      
          public String getName() {
              return name;
          }
      
          public void setName(String name) {
              this.name = name;
          }
      
          public Node getLeft() {
              return left;
          }
      
          public void setLeft(Node left) {
              this.left = left;
          }
      
          public Node getRight() {
              return right;
          }
      
          public void setRight(Node right) {
              this.right = right;
          }
      
          public Node() {
          }
      
          public Node(int id, String name) {
              this.id = id;
              this.name = name;
          }
      
          //    先序遍历
          public void preOrder() {
              System.out.println(this);
              if (this.left != null) {
                  this.left.preOrder();
              }
              if (this.right != null) {
                  this.right.preOrder();
              }
          }
          public void infixOrder(){
              if (this.left!=null){
                  this.left.infixOrder();
              }
              System.out.println(this);
              if (this.right != null) {
                  this.right.preOrder();
              }
          }
          public void postOrder(){
              if (this.left!=null){
                  this.left.postOrder();
              }
              if (this.right != null) {
                  this.right.postOrder();
              }
              System.out.println(this);
          }
      
          public Node preFind(Node node){
              if (this.id==node.id){
                  return this;
              }
              if (this.left!=null){
                  return this.left.preFind(node);
              }
              if (this.right!=null){
                  return this.right.preFind(node);
              }
              return null;
          }
      }
  4. 二叉树的查找:

    1.  

       

    2. package com.model.tree;
      
      /**
       * @Description:测试类
       * @Author: 张紫韩
       * @Crete 2021/7/13 18:54
       * 演示二叉树的遍历
       */
      public class TreeDemo01 {
          public static void main(String[] args) {
      
              Node node1 = new Node(1, "张紫韩1");
              Node node2 = new Node(2, "张紫韩2");
              Node node3 = new Node(3, "张紫韩3");
              Node node4 = new Node(4, "张紫韩4");
              Node node5 = new Node(5, "张紫韩5");
              node1.setLeft(node2);
              node1.setRight(node3);
              node3.setRight(node4);
              node3.setLeft(node5);
              BinaryTree tree = new BinaryTree(node1);
      //        三种遍历
              tree.perOrder();
              tree.infixOrder();
              tree.postOrder();
      //        三种查找
              System.out.println("----------------");
              System.out.println(tree.preFind(4));
              System.out.println("----------------");
              System.out.println(tree.infixFind(4));
              System.out.println("----------------");
              System.out.println(tree.postFind(5));
          }
      }
      
      class BinaryTree {
          public Node root;
      
          public BinaryTree(Node root) {
              this.root = root;
          }
      
          //   遍历这个树
          public void perOrder() {
              if (root != null) {
                  root.preOrder();
              } else {
                  System.out.println("当前的树为空");
              }
          }
      
          public void infixOrder() {
              if (root != null) {
                  root.infixOrder();
              } else {
                  System.out.println("当前的树为空");
              }
          }
      
          public void postOrder() {
              if (root != null) {
                  root.postOrder();
              } else {
                  System.out.println("当前的树为空");
              }
          }
      
          public Node preFind(int id) {
              if (root != null) {
                  return root.preFind(id);
              } else {
                  System.out.println("该节点为空");
                  return null;
              }
          }
      
          public Node infixFind(int id) {
              if (root != null) {
                  return root.infixFind(id);
              } else {
                  System.out.println("该节点为空");
                  return null;
              }
          }
      
          public Node postFind(int id) {
              if (root != null) {
                  return root.postFind(id);
              } else {
                  System.out.println("该节点为空");
                  return null;
              }
          }
      }
      
      class Node {
          private int id;
          private String name;
          private Node left;
          private Node right;
      
          @Override
          public String toString() {
              return "Node{" +
                      "id=" + id +
                      ", name='" + name + '\'' +
                      '}';
          }
      
          public int getId() {
              return id;
          }
      
          public void setId(int id) {
              this.id = id;
          }
      
          public String getName() {
              return name;
          }
      
          public void setName(String name) {
              this.name = name;
          }
      
          public Node getLeft() {
              return left;
          }
      
          public void setLeft(Node left) {
              this.left = left;
          }
      
          public Node getRight() {
              return right;
          }
      
          public void setRight(Node right) {
              this.right = right;
          }
      
          public Node() {
          }
      
          public Node(int id, String name) {
              this.id = id;
              this.name = name;
          }
      
          //    先序遍历
          public void preOrder() {
              System.out.println(this);
              if (this.left != null) {
                  this.left.preOrder();
              }
              if (this.right != null) {
                  this.right.preOrder();
              }
          }
      
          public void infixOrder() {
              if (this.left != null) {
                  this.left.infixOrder();
              }
              System.out.println(this);
              if (this.right != null) {
                  this.right.preOrder();
              }
          }
      
          public void postOrder() {
              if (this.left != null) {
                  this.left.postOrder();
              }
              if (this.right != null) {
                  this.right.postOrder();
              }
              System.out.println(this);
          }
      
          //    前序查找
          public Node preFind(int id) {
              System.out.println("前序查找进行了比较");
              if (this.id == id) {
                  return this;
              }
              Node temp = null;
              if (this.left != null) {
                  temp = this.left.preFind(id);
              }
              if (temp != null) {
                  return temp;
              }
              if (this.right != null) {
                  temp = this.right.preFind(id);
              }
              return temp;
          }
      
          //    中序查找
          public Node infixFind(int id) {
              Node temp = null;
              if (this.left != null) {
                  temp = this.left.infixFind(id);
              }
              if (temp != null) return temp;
              System.out.println("中序查找进行比较了");
              if (this.id == id) {
                  return this;
              }
              if (this.right != null) {
                  temp = this.right.infixFind(id);
              }
              return temp;
      
          }
      
          //    后序查找
          public Node postFind(int id) {
              Node temp = null;
              if (this.left != null) {
                  temp = this.left.postFind(id);
              }
              if (temp != null) return temp;
              if (this.right != null) {
                  temp = this.right.postFind(id);
              }
              if (temp != null) return temp;
              System.out.println("后序查找进行比较了");
              if (this.id == id) {
                  return this;
              }
              return null;
          }
      }
  5. 二叉树删除节点:

    1.  
    2.     //    递归删除节点
          public void delNode(int id) {
              if (this.left != null && this.left.id == id) {
                  this.left = null;
                  return;
              }
              if (this.right != null && this.right.id == id) {
                  this.right = null;
                  return;
              }
              if (this.left!=null){
                  this.left.delNode(id);
              }
              if (this.right!=null){
                  this.right.delNode(id);
              }
          }
      //    删除节点
          public void delNode(int id){
              if (root==null||root.getId()==id){
                  root=null;
              }else {
                  root.delNode(id);
              }
          }
    3.  

    4.  

        public void delNode01(int id) {
              if (this.left != null && this.left.id == id) {
                  if (this.left.left!=null){
                      this.left = this.left.left;
                  }else if (this.left.left==null&&this.left.right!=null){
                      this.left=this.left.right;
                  }else{
                      this.left=null;
                  }
      
                  return;
              }
              if (this.right != null && this.right.id == id) {
                  if (this.right.left!=null){
                      this.right = this.right.left;
                  }else if (this.right.left==null&&this.right.right!=null){
                      this.right=this.right.right;
                  }else{
                      this.right=null;
                  }
                  return;
              }
              if (this.left!=null){
                  this.left.delNode(id);
              }
              if (this.right!=null){
                  this.right.delNode(id);
              }
          }

       

       

posted @ 2021-07-13 21:54  张紫韩  阅读(76)  评论(0编辑  收藏  举报