二叉排序树BST代码（JAVA）

 

 

1. publicclassTest{
3.     publicstaticvoid main(String[] args){
4.         int[] r =newint[]{5,1,3,4,6,7,2,8,9,0};
5.         BST binarySearchTree =new BST(r);
6.         binarySearchTree.inOrder();
7.         System.out.println();
8.         binarySearchTree.searchBST(6);//查找成功
9.         System.out.println();
10.         binarySearchTree.searchBST(10);//查找失败->插入
11.         System.out.println();
12.     }
13.  
14. }

 

 

1. publicclass BST {
2.  
3.     //二叉树结点
4.     publicclassBiNode{
5.         int data;
6.         BiNode left;
7.         BiNode right;
8.  
9.         BiNode(int data,BiNode left,BiNode right){
10.             this.data = data;
11.             this.left = left;
12.             this.right = right;
13.         }
14.     }
15.  
16.     privateBiNode root = null;
17.  
18.     BST(int[] r)
19.     {
20.         for(int i =0; i < r.length; i++)
21.         {
22.             BiNode s =newBiNode(r[i],null,null);
23.             root = insertBST(root, s);
24. //            insertBST1(s);
25.         }
26.     }
27.  
28.     //插入（递归）
29.     publicBiNode insertBST(BiNode head,BiNode s)
30.     {
31.         if(head == null){
32.             head = s;
33.             return head;
34.         }
35.  
36.         if(s.data < head.data)
37.             head.left = insertBST(head.left, s);
38.         else
39.            head.right = insertBST(head.right,s);
40.  
41.         return  head;
42.     }
43.  
44.     //插入（非递归：循环、用临时变量保存过程）
45.     publicvoid insertBST1(BiNode s)
46.     {
47.         if(root == null){
48.             root = s;
49.             return;
50.         }
51.  
52.         BiNode temp = root;//需要临时结点记录
53.  
54.         while(true)
55.         {
56.             if(s.data < temp.data)
57.             {
58.                 if(temp.left == null)
59.                 {
60.                     temp.left = s;
61.                     return;
62.                 }
63.                 temp = temp.left;
64.             }
65.             else
66.             {
67.                 if(temp.right == null)
68.                 {
69.                     temp.right = s;
70.                     return;
71.                 }
72.                 temp = temp.right;
73.             }
74.         }
75.     }
76.  
77.  
78.     //查找：成功->返回；失败：插入
79.     publicBiNode searchBST(int a)
80.     {
81.         BiNode s1 = searchBST(root,a);
82.         if(s1 == null){
83.             BiNode s2 =newBiNode(a,null,null);
84.             insertBST1(s2);
85.             System.out.println("search fail ; insert success: "+ s2.data);
86.             inOrder();
87.             return s2;
88.         }else{
89.             System.out.println("search success: "+ s1.data);
90.             return s1;
91.         }
92.     }
93.     //查找
94.     privateBiNode searchBST(BiNode head,int a)
95.     {
96.         if(head == null)
97.             return null;
98.  
99.         if(a < head.data)
100.             return searchBST(head.left, a);
101.         elseif(a > head.data)
102.             return searchBST(head.right, a);
103.         else
104.             return head;
105.     }
106.  
107. //    删除
108. //    删除f的孩子p
109.     publicvoid deleteLeftBST(BiNode f,BiNode p)
110.     {
111.         if(p.left == null && p.right == null)    //p为叶子
112.         {
113.             f.left = null;
114.             p = null;
115.         }
116.         elseif(p.right == null)                  //p只有左子树
117.         {
118.             f.left = p.left;
119.             p = null;
120.         }
121.         elseif(p.left == null)                  //p只有右子树
122.         {
123.             f.left = p.right;
124.             p = null;
125.         }
126.         else                                       //p的左右子树均不空
127.         {
128.             BiNode par = p, s = par.right;          //用par s 去查找p的右子树的最左下结点
129.             while(s.left != null)
130.             {
131.                 par = s;
132.                 s = par.left;
133.             }
134.             p.data = s.data;                       //交换最左下结点s与p结点数据
135.  
136.                                                     //剪枝（删除s结点）
137.             if(par == p)                          //处理特殊情况
138.             {
139.                 par.right = s.right;
140.                 s = null;
141.             }
142.             else                                   //处理一般情况
143.             {
144.                 par.left = s.right;
145.                 s = null;
146.             }
147.  
148.         }
149.     }
150.  
151.     //先序遍历
152.     publicvoid preOrder(){
153.         System.out.print("preOrder traversal with recursion:");
154.         preOrder(root);
155.         System.out.println();
156.     }
157.     //递归
158.     privatevoid preOrder(BiNode root){
159.         if(root == null)return;
160.  
161.         System.out.print(root.data);       //访问结点
162.         preOrder(root.left);
163.         preOrder(root.right);
164.     }
165.  
166.     //中序遍历
167.     publicvoid inOrder(){
168.         System.out.print("inOrder traversal with recursion:");
169.         inOrder(root);
170.         System.out.println();
171.     }
172.     //递归
173.     privatevoid inOrder(BiNode root){
174.         if(root == null)//访问结点
175.             return;
176.  
177.         inOrder(root.left);
178.         System.out.print(root.data);      //访问结点
179.         inOrder(root.right);
180.     }
181.  
182.     //后序遍历
183.     publicvoid postOrder(){
184.         System.out.print("postOrder traversal with recursion:");
185.         postOrder(root);
186.         System.out.println();
187.     }
188.     //递归
189.     privatevoid postOrder(BiNode root){
190.         if(root == null)return;
191.  
192.         postOrder(root.left);
193.         postOrder(root.right);
194.         System.out.print(root.data);     //访问结点
195.     }
196. }

 

输出：

1. inOrder traversal with recursion:0123456789
2.  
3. search success:6
4.  
5. search fail ; insert success:10
6. inOrder traversal with recursion:012345678910

 

 

 

来自为知笔记(Wiz)