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【c++模板实现】二叉查找树

捣鼓了一个晚上，最后还是照着书本把这BST弄出来了。悲催的娃娃啊，不动手写这个还真的很难啊！

BSTree.h 
  1 #ifndef BTREE_H_
  2 #define BTREE_H_
  3 
  4 #include <iostream>
  5 using std::ostream;
  6 
  7 template <class TreeDataType>
  8 class BSTree
  9 {
 10 private:
 11     class BSTNode
 12     {
 13     public:
 14         BSTNode* left;
 15         BSTNode* right;
 16         TreeDataType data; BSTNode():left(NULL),right(NULL) {}
 17         BSTNode(TreeDataType a_data):data(a_data),left(NULL),right(NULL) {}
 18     };//节点声明
 19     typedef BSTNode* BSTNodePointer;
 20     BSTNodePointer m_root;
 21 
 22 public:
 23     BSTree():m_root(NULL) {}
 24     ~BSTree() {deleteNode(m_root);}
 25     bool isEmpty() const {return m_root == NULL;}
 26     bool find(const TreeDataType& a_data) const;
 27     void insert(const TreeDataType& a_data) {insertAux(m_root,a_data);}
 28     void remove(const TreeDataType& a_data);
 29     void inorder(ostream& out) const {inorderAux(out, m_root);}
 30     void graph(ostream& out) const {graphAux(out, 0, m_root);}
 31 
 32 protected:
 33     void deleteNode(BSTNodePointer a_node);//删除节点和所有到子节点
 34     void insertAux(BSTNodePointer& a_subRoot, const TreeDataType& a_data);
 35     void inorderAux(ostream& out, BSTNodePointer a_subRoot) const;
 36     void graphAux(ostream& out, int a_indent, BSTNodePointer a_subRoot) const;
 37     void find2(const TreeDataType& a_data, bool& found, BSTNodePointer& a_locPtr, BSTNodePointer& a_parent) const; 
 38 };//类模板声明结束
 39 #endif
 40 
 41 template <class TreeDataType>
 42 inline void BSTree<TreeDataType>::deleteNode(BSTree<TreeDataType>::BSTNodePointer a_node)
 43 {
 44     if (a_node->left != NULL)
 45     {
 46         deleteNode(a_node->left);
 47     }
 48     else if (a_node->right != NULL)
 49     {
 50         deleteNode(a_node->right);
 51     }
 52     else if (a_node != NULL)
 53     {
 54         delete a_node;
 55         a_node = NULL;
 56     }
 57 }
 58 
 59 template <class TreeDataType>
 60 inline void BSTree<TreeDataType>::insertAux(BSTree<TreeDataType>::BSTNodePointer& a_subRoot, const TreeDataType& a_data)
 61 {
 62     if (a_subRoot == NULL)
 63     {
 64         a_subRoot = new BSTree<TreeDataType>::BSTNode(a_data);
 65     }
 66     else if (a_data < a_subRoot->data)
 67     {
 68         insertAux(a_subRoot->left,a_data);
 69     }
 70     else if (a_subRoot->data < a_data)
 71     {
 72         insertAux(a_subRoot->right,a_data);
 73     }
 74     else
 75     {
 76         std::cerr << "a_data already in the tree!\n";
 77     }
 78 }
 79 
 80 template <class TreeDataType>
 81 inline void BSTree<TreeDataType>::inorderAux(ostream& out, BSTree<TreeDataType>::BSTNodePointer a_subRoot) const
 82 {
 83     if (a_subRoot != NULL)
 84     {
 85         inorderAux(out, a_subRoot->left);//L
 86         out << a_subRoot->data << " ";//V
 87         inorderAux(out, a_subRoot->right);//R
 88     }
 89 }
 90 
 91 #include <iomanip>
 92 using std::setw;
 93 using std::endl;
 94 template <class TreeDataType>
 95 inline void BSTree<TreeDataType>::graphAux(ostream& out, int a_indent, BSTree<TreeDataType>::BSTNodePointer a_subRoot) const
 96 {
 97     if (a_subRoot != NULL)
 98     {
 99         graphAux(out, a_indent+8, a_subRoot->right);                //R
100         out << setw(a_indent) << " " << a_subRoot->data << endl;    //V
101         graphAux(out, a_indent+8, a_subRoot->left);                    //L
102     }
103 }
104 
105 template <class TreeDataType>
106 inline bool BSTree<TreeDataType>::find(const TreeDataType& a_data) const
107 {
108     BSTree<TreeDataType>::BSTNodePointer locPtr = m_root;
109     bool found = false;
110     while (!found && locPtr != NULL)
111     {
112         if (a_data < locPtr->data)
113         {
114             locPtr = locPtr->left;
115         }
116         else if (locPtr->data < a_data)
117         {
118             locPtr = locPtr->right;
119         }
120         else
121         {
122             found = true;
123         }
124     }
125     return found;
126 }
127 
128 template <class TreeDataType>
129 inline void BSTree<TreeDataType>::find2(const TreeDataType& a_data, bool& found, 
130                                 BSTree<TreeDataType>::BSTNodePointer& a_locPtr,
131                                 BSTree<TreeDataType>::BSTNodePointer& a_parent) const
132 {
133     a_locPtr = m_root;
134     a_parent = NULL;
135     found = false;
136     while (!found && a_locPtr != NULL)
137     {
138         if (a_data < a_locPtr->data)
139         {
140             a_parent = a_locPtr; 
141             a_locPtr = a_locPtr->left;
142         }
143         else if (a_locPtr->data < a_data)
144         {
145             a_parent = a_locPtr; 
146             a_locPtr = a_locPtr->right;
147         }
148         else
149         {
150             found = true;
151         }
152     }
153 }
154 
155 template <class TreeDataType>
156 inline void BSTree<TreeDataType>::remove(const TreeDataType& a_data)
157 {
158     bool found = false;
159     BSTree<TreeDataType>::BSTNodePointer x; //被删除的节点
160     BSTree<TreeDataType>::BSTNodePointer parent;
161     find2(a_data,found,x,parent);
162     if (!found)
163     {
164         std::cerr << "a_data is not in the tree!\n";
165         return;
166     }
167     
168     if (x->left != NULL && x->right != NULL)//节点有两个子女
169     {
170         //查找x的中续后继节点及其双亲节点
171         BSTree<TreeDataType>::BSTNodePointer xSucc = x->right;
172         parent = x;
173         while (xSucc->left != NULL)
174         {
175             parent = xSucc;
176             xSucc = xSucc->left;
177         }
178         x->data = xSucc->data;
179         x = xSucc;
180     }
181     BSTree<TreeDataType>::BSTNodePointer subTree = x->left;
182     if (subTree == NULL)
183     {
184         subTree = x->right;
185     }
186     if (parent == NULL)
187     {
188         m_root = subTree;
189     }
190     else if (parent->left == x)
191     {
192         parent->left = subTree;
193     }
194     else
195     {
196         parent->right = subTree;
197     }
198     delete x;
199 }

测试下结果

test.cpp 
 1 #include "BSTree.h"
 2 #include <cstdlib>
 3 #include <iostream>
 4 using namespace std;
 5 
 6 int main()
 7 {
 8     BSTree<int> intBST;
 9     cout << "Constructing empty BST\n";
10     cout << "BST " << (intBST.isEmpty()?"is":"is not") << "empty\n";
11 
12     int number;
13     for (;;)
14     {
15         cout << "Item to insert (-999 to stop):";
16         cin >> number;
17         if (number == -999) break;
18         intBST.insert(number);
19     }
20     intBST.inorder(cout);
21     cout << endl;
22     intBST.graph(cout);
23     
24     //测试find
25     for (;;)
26     {
27         cout << "Item to find (-999 to stop):";
28         cin >> number;
29         if (number == -999) break;
30         bool found = intBST.find(number);
31         cout << boolalpha << found << endl;
32     }
33     
34     //测试remove
35     for (;;)
36     {
37         cout << "Item to remove (-999 to stop):";
38         cin >> number;
39         if (number == -999) break;
40         intBST.remove(number);
41         cout << endl;
42         intBST.graph(cout);
43         cout << endl;
44     }
45     intBST.inorder(cout);
46     return 0;
47 }
posted @ 2012-08-18 22:53  涵曦  阅读(1356)  评论(0)  编辑  收藏  举报