二叉树学习一：二叉树创建与遍历

 1 #include<iostream>
 2 using namespace std;
 3 
 4 typedef struct BiTreeNode{
 5     char data;
 6     BiTreeNode* pLchild;
 7     BiTreeNode* pRchild;
 8 }BiTreeNode, *BiTree;
 9 
10 //创建二叉树
11 void  CreateBiTree(BiTree &pTree){
12     char ch;
13     cin >> ch;
14     if (ch == ‘*‘)
15     {
16         pTree = NULL;
17     }
18     else
19     {
20         pTree = new BiTreeNode;
21         pTree->data = ch;
22         CreateBiTree(pTree->pLchild);
23         CreateBiTree(pTree->pRchild);
24     }
25 }
26 
27 //先序遍历二叉树
28 void PreOrderTrav(BiTree &pTree){
29     if (pTree != NULL)
30     {
31         cout << pTree->data << ‘\t‘;
32         PreOrderTrav(pTree->pLchild);
33         PreOrderTrav(pTree->pRchild);
34     }
35 }
36 
37 //中序遍历
38 void InOrderTrav(BiTree &pTree){
39     if (pTree != NULL)
40     {
41         InOrderTrav(pTree->pLchild);
42         cout << pTree->data << ‘\t‘;
43         InOrderTrav(pTree->pRchild);
44     }
45 }
46 
47 //后序遍历
48 void PosOrderTrav(BiTree &pTree){
49     if (pTree != NULL)
50     {
51         PosOrderTrav(pTree->pLchild);
52         PosOrderTrav(pTree->pRchild);
53         cout << pTree->data << ‘\t‘;
54     }
55 }
56 
57 void main()
58 {
59     BiTree pTree = NULL;
60     CreateBiTree(pTree);
61     cout << "先序遍历：" << endl;
62     PreOrderTrav(pTree);
63     cout << endl << "中序遍历：" << endl;
64     InOrderTrav(pTree);
65     cout << endl << "后序遍历：" << endl;
66     PosOrderTrav(pTree);
67     cout << endl;
68 }