二叉树的基本遍历操作
2011-08-25 19:22 Daniel Zheng 阅读(402) 评论(0) 编辑 收藏 举报1 #include <queue>
2 #include <iostream>
3 using namespace std;
4
5 #define QSIZE 100
6 struct BTree
7
8 {
9 int value;
10 struct BTree* lChild;
11 struct BTree* rChild;
12 };
13
14 void VisitNode(BTree * T)
15 {
16 cout<<T->value<<" ";
17 }
18 BTree * Insert(BTree* T, int value) //T is the root of binary tree
19 {
20 if(T == NULL)
21 {
22 T = new BTree;
23 if( T == NULL)
24 cout<<"Malloc Failed."<<endl;
25 else
26 {
27 T->value = value;
28 T->lChild = T->rChild = NULL;
29 }
30 }
31 else if(value < T->value)
32 T->lChild = Insert(T->lChild,value);
33 else if(value > T->value)
34 T->rChild = Insert(T->rChild, value);
35 return T;
36 }
37
38 BTree* MakeEmpty(BTree* T)
39 {
40 if(T != NULL)
41 {
42 MakeEmpty(T->lChild);
43 MakeEmpty(T->rChild);
44 delete T;
45 }
46 return NULL;
47 }
48
49 void LevelTraversal(BTree * T)
50 {
51 if(T == NULL)
52 return;
53 queue<BTree> Queue;
54 Queue.push(*T);
55 while(!Queue.empty())
56 {
57 VisitNode(&Queue.front());
58 if(Queue.front().lChild != NULL)
59 Queue.push(*Queue.front().lChild);
60 if(Queue.front().rChild != NULL)
61 Queue.push(*Queue.front().rChild);
62 Queue.pop();
63 }
64 }
65
66 void PreOrder(BTree * T)
67 {
68 if(T == NULL)
69 return;
70 VisitNode(T);
71 PreOrder(T->lChild);
72 PreOrder(T->rChild);
73 }
74
75 void InOrder(BTree * T)
76 {
77 if(T == NULL)
78 return;
79 InOrder(T->lChild);
80 VisitNode(T);
81 InOrder(T->rChild);
82 }
83
84 void PosOrder(BTree * T)
85 {
86 if(T == NULL)
87 return;
88 PosOrder(T->lChild);
89 PosOrder(T->rChild);
90 VisitNode(T);
91 }
92
93 int HeightofBTree(BTree * T)
94 {
95 if(T == NULL)
96 return 0;
97
98 int hLeft = HeightofBTree(T->lChild);
99 int hRight = HeightofBTree(T->rChild);
100 return (hLeft > hRight ? hLeft : hRight) + 1;
101 }
102
103 int main()
104 {
105 BTree* T = NULL;
106 T = Insert(T,45);
107 T = Insert(T,21);
108 T = Insert(T,65);
109 T = Insert(T,10);
110 T = Insert(T,50);
111 T = Insert(T,70);
112 T = Insert(T,24);
113
114 cout<<"Level Traversal:";
115 LevelTraversal(T);
116 cout<<endl;
117
118 cout<<"Preorder Traversal:";
119 PreOrder(T);
120 cout<<endl;
121
122 cout<<"Inorder Traversal:";
123 InOrder(T);
124 cout<<endl;
125
126 cout<<"Posorder Traversal:";
127 PosOrder(T);
128 cout<<endl;
129
130 cout<<"Height of BTree is "<<HeightofBTree(T);
131
132 MakeEmpty(T);
133 cout<<endl;
134 return 0;
135 }
建立一个二分排序树，注意二叉树内存空间的递归释放。
