java数据结构之二叉树的实现

java二叉树的简单实现，可以简单实现深度为n的二叉树的建立，二叉树的前序遍历，中序遍历，后序遍历输出。
 1 /**
 2  *数据结构之树的实现
 3  *2016/4/29
 4  *
 5  **/
 6 package cn.Link;
 7 
 8 public class Tree {
 9     Node head = new Node();
10     Tree(){} 
11 
12     //内部节点类
13     class Node{
14         String date;
15         Node left;
16         Node right;
17         Node(){ }
18         Node(String date){
19             this.date = date;
20             this.left = null;
21             this.right = null;
22         }
23     }
24 
25     //给深度为n的满二叉树添加数据  n表示数的深度
26     public void addTree(Node preNode,int n){
27         if(n ==1) return;
28         preNode.date = "sum"+n;
29         Node preNodeLeft = new Node();
30         Node preNodeRight = new Node();
31         
32         preNode.left = preNodeLeft;
33         addTree(preNodeLeft,n-1);
34         preNode.right = preNodeRight;
35         addTree(preNodeRight,n-1);
36     }
37 
38     //前序遍历二叉树  并输出
39     public void printTreePre(Node preNode){
40         if(preNode == null) return;
41         if(preNode.left!=null || preNode.right!=null)
42         System.out.print(preNode.date+"  ");
43 
44         printTreePre(preNode.left);
45         printTreePre(preNode.right);
46     }   
47     
48     //中序遍历二叉树  并输出
49     public void printTreeAmong(Node preNode){
50         if(preNode == null) return;
51         printTreeAmong(preNode.left);
52         if(preNode.left!=null || preNode.right!=null)
53         System.out.print(preNode.date+"  ");
54         printTreeAmong(preNode.right);
55     }   
56 
57     //后序遍历二叉树  并输出
58     public void printTreeRear(Node preNode){
59         if(preNode == null) return;
60         printTreeRear(preNode.left);
61         printTreeRear(preNode.right);
62 
63         if(preNode.left!=null || preNode.right!=null)
64         System.out.print(preNode.date+"  ");
65     }   
66 
67 
68     //测试函数
69     public static void main(String [] args){
70     Tree tree = new Tree();
71     tree.addTree(tree.head,4);
72     System.out.println("================前序遍历================");
73     tree.printTreePre(tree.head);
74     System.out.println();
75     System.out.println("================中序遍历===============");
76     tree.printTreeAmong(tree.head);
77     System.out.println();
78     System.out.println("================后序遍历===============");
79     tree.printTreeRear(tree.head);
80     System.out.println();
81     System.out.println("============手工输出所有数据===========");
82     System.out.println(tree.head.date);
83     System.out.println(tree.head.left.date+" "+tree.head.right.date);
84     System.out.println(tree.head.left.left.date+"  "+tree.head.left.right.date+"   "+tree.head.right.left.date+"   "+tree.head.right.right.date);
85     }
86 }
posted on 2016-04-29 15:53 snail-lb 阅读(233) 评论(0) 编辑收藏举报