(1)结构体和类定义
struct BTreeNode {
T data;
BTreeNode* left, * right;
BTreeNode() :data(0), left(nullptr), right(nullptr) {}
BTreeNode(T val, BTreeNode<T>* leftChild = nullptr, BTreeNode<T>* rightChild = nullptr)
:data(val), left(leftChild), right(rightChild) {}
};
template<class T>
class BTree {
public:
BTree() :root(nullptr) {} // 构造函数
BTree(string str); // 重载
void createTree(BTreeNode<T>*& bt, string str); // 创建二次树
~BTree(); // 析构函数
bool IsEmpty(); // 判二叉树空否?
int Size(BTreeNode<T>* cur); // 计算结点个数
int getSize(); // 获取结点个数
BTreeNode<T>* getData(T& item, BTreeNode<T>* cur); // 取得结点数据
bool Find(T& item); // 判断item是否在树中
int Height(BTreeNode<T>* bt); // 求树高度
int getHeight(); // 获取树高度
BTreeNode<T>* getRoot(); // 取根
void preOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 前序遍历
void inOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 中序遍历
void postOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 后序遍历
void levelOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 层序遍历
vector<T> preOrder(); // 调用前序遍历,返回vector
vector<T> inOrder(); // 调用中序遍历,返回vector
vector<T> postOrder(); // 调用后序遍历,返回vector
vector<T> levelOrder(); // 调用层序遍历,返回vector
void CopyTree(BTreeNode<T>* root, BTreeNode<T>*& copyRoot); // 二叉树复制
void Copy(BTreeNode<T>*& copyRoot); // 调用二叉树复制
void destroyCopyTree(BTreeNode<T>*& copyRoot); // 销毁复制二叉树
BTreeNode<T>* FindParent(BTreeNode<T>* root, BTreeNode<T>* node); // 寻找双亲
BTreeNode<T>* LeftChild(BTreeNode<T>* node) { //求结点 node 的左孩子
return (node != nullptr) ? node->left : nullptr;
}
BTreeNode<T>* RightChild(BTreeNode<T>* node) { //求结点 node 的右孩子
return (node != nullptr) ? node->right : nullptr;
}
protected:
BTreeNode<T>* root;
void destroyTree(BTreeNode<T>* node); // 销毁二叉树
};
(2)创建二叉树
template<class T>
BTree<T>::BTree(string str) {
createTree(root, str);
cout << "报告:创建一颗二叉树,完成!!!" << endl;
}
template<class T>
void BTree<T>::createTree(BTreeNode<T>*& bt, string str) {
static int i = 0;
char ch = ' ';
ch = str[i++];
if (ch == '#') bt = nullptr;
else {
bt = new BTreeNode<T>(ch);
createTree(bt->left, str);
createTree(bt->right, str);
}
};
(3)前中后序遍历和层序遍历
// 前序遍历
template<class T>
void BTree<T>::preOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
vec.push_back(cur->data); // 中
preOrderTraversal(cur->left, vec); // 左
preOrderTraversal(cur->right, vec); // 右
}
// 调用前序遍历,返回vector
template<class T>
vector<T> BTree<T>::preOrder() {
cout << "获取前序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
preOrderTraversal(root, resVec);
return resVec;
}
// 中序遍历
template<class T>
void BTree<T>::inOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
inOrderTraversal(cur->left, vec); // 左
vec.push_back(cur->data); // 中
inOrderTraversal(cur->right, vec); // 右
}
// 调用中序遍历,返回vector
template<class T>
vector<T> BTree<T>::inOrder() {
cout << "获取中序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
inOrderTraversal(root, resVec);
return resVec;
}
// 后序遍历
template<class T>
void BTree<T>::postOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
postOrderTraversal(cur->left, vec); // 左
postOrderTraversal(cur->right, vec); // 右
vec.push_back(cur->data); // 中
}
// 调用后序遍历,返回vector
template<class T>
vector<T> BTree<T>::postOrder() {
cout << "获取后序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
postOrderTraversal(root, resVec);
return resVec;
}
// 层序遍历
template<class T>
void BTree<T>::levelOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr) return;
queue<BTreeNode<T>*> Queue;
BTreeNode<T>* p;
Queue.push(cur); // 根结点入队列
while (!Queue.empty()) {
p = Queue.front();
//cout << p->data << " ";//输出出队结点的数据
vec.push_back(p->data);
Queue.pop();
if (p->left != nullptr) {
Queue.push(p->left);
}
if (p->right != nullptr) {
Queue.push(p->right);
}
}
}
// 调用层序遍历,返回vector
template<class T>
vector<T> BTree<T>::levelOrder() {
cout << "获取层序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
levelOrderTraversal(root, resVec);
return resVec;
}
(4)复制二叉树
template<class T>
void BTree<T>::CopyTree(BTreeNode<T>* root, BTreeNode<T>*& copyRoot) {
if (!root) {
copyRoot = nullptr;
}
else {
copyRoot = new BTreeNode<T>;
copyRoot->data = root->data; //复制根节点
CopyTree(root->left, copyRoot->left); //递归复制左子树
CopyTree(root->right, copyRoot->right);//递归复制左子树
}
}
template<class T>
void BTree<T>::Copy(BTreeNode<T>*& copyRoot) {
CopyTree(root, copyRoot);
}
(5)销毁二叉树
template<class T>
void BTree<T>::destroyCopyTree(BTreeNode<T>*& copyRoot) {
destroyTree(copyRoot);
cout << "报告,复制二叉树已销毁完毕!!!" << endl;
}
// 销毁二叉树
template<class T>
void BTree<T>::destroyTree(BTreeNode<T>* bt) {
// 后序遍历删除根为subTree的子树;
if (bt != nullptr) {
destroyTree(bt->left); //删除左子树
destroyTree(bt->right); //删除右子树
delete bt; //删除根结点
}
}
(6)析构函数
// 析构函数
template<class T>
BTree<T>::~BTree<T>() {
//cout << "调用析构函数" << endl;
destroyTree(root);
cout << "报告,这棵树已经销毁完毕!!!" << endl;
}
(7)求树的高度
// 求树高度
template<class T>
int BTree<T>::Height(BTreeNode<T>* bt) {
if (bt == nullptr) return 0;
else {
int leftH = Height(bt->left);
int rightH = Height(bt->right);
return (leftH > rightH) ? leftH + 1 : rightH + 1;
}
}
// 获取树高度
template<class T>
int BTree<T>::getHeight() {
return Height(root);
}
(8)获取结点,判断其是否在二叉树中
// 取得结点数据
template<class T>
BTreeNode<T>* BTree<T>::getData(T& item, BTreeNode<T>* cur) {
if (cur == nullptr) return nullptr;
if (cur->data == item) return cur;
return getData(item, cur->left) != nullptr ? getData(item, cur->left) : getData(item, cur->right);
}
// 判断item是否在树中
template<class T>
bool BTree<T>::Find(T& item) {
if (this->getData(item, root) == nullptr) return false;
else return true;
(9)计算结点个数和获取结点个数
// 计算结点个数
template<class T>
int BTree<T>::Size(BTreeNode<T>* cur) {
if (cur == nullptr)
return 0;
else
return 1 + Size(cur->left) + Size(cur->right);
}
// 获取结点个数
template<class T>
int BTree<T>::getSize() {
return Size(root);
}
(10)二叉树判空
// 判二叉树空否?
template<class T>
bool BTree<T>::IsEmpty() {
return (root == nullptr) ? true : false;
}
(11)获取根结点
// 获取根
template<class T>
BTreeNode<T>* BTree<T>::getRoot() {
if (!root) return nullptr;
else {
return this->root;
}
}
源代码:
btree.h
#pragma once
#include <iostream>
#include <vector>
#include <queue>
using namespace std;
template<class T>
struct BTreeNode {
T data;
BTreeNode* left, * right;
BTreeNode() :data(0), left(nullptr), right(nullptr) {}
BTreeNode(T val, BTreeNode<T>* leftChild = nullptr, BTreeNode<T>* rightChild = nullptr)
:data(val), left(leftChild), right(rightChild) {}
};
template<class T>
class BTree {
public:
BTree() :root(nullptr) {} // 构造函数
BTree(string str); // 重载
void createTree(BTreeNode<T>*& bt, string str); // 创建二次树
~BTree(); // 析构函数
bool IsEmpty(); // 判二叉树空否?
int Size(BTreeNode<T>* cur); // 计算结点个数
int getSize(); // 获取结点个数
BTreeNode<T>* getData(T& item, BTreeNode<T>* cur); // 取得结点数据
bool Find(T& item); // 判断item是否在树中
int Height(BTreeNode<T>* bt); // 求树高度
int getHeight(); // 获取树高度
BTreeNode<T>* getRoot(); // 取根
void preOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 前序遍历
void inOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 中序遍历
void postOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 后序遍历
void levelOrderTraversal(BTreeNode<T>* cur, vector<int>& vec); // 层序遍历
vector<T> preOrder(); // 调用前序遍历,返回vector
vector<T> inOrder(); // 调用中序遍历,返回vector
vector<T> postOrder(); // 调用后序遍历,返回vector
vector<T> levelOrder(); // 调用层序遍历,返回vector
void CopyTree(BTreeNode<T>* root, BTreeNode<T>*& copyRoot); // 二叉树复制
void Copy(BTreeNode<T>*& copyRoot); // 调用二叉树复制
void destroyCopyTree(BTreeNode<T>*& copyRoot); // 销毁复制二叉树
BTreeNode<T>* FindParent(BTreeNode<T>* root, BTreeNode<T>* node); // 寻找双亲
BTreeNode<T>* LeftChild(BTreeNode<T>* node) { //求结点 node 的左孩子
return (node != nullptr) ? node->left : nullptr;
}
BTreeNode<T>* RightChild(BTreeNode<T>* node) { //求结点 node 的右孩子
return (node != nullptr) ? node->right : nullptr;
}
protected:
BTreeNode<T>* root;
void destroyTree(BTreeNode<T>* node); // 销毁二叉树
};
btree.cpp
// 每次写递归,都按照这三要素来写,可以保证大家写出正确的递归算法!
// 1.确定递归函数的参数的返回值
// 2.确定终止条件
// 3.确定单层递归的逻辑
#include "btree.h"
template<class T>
BTree<T>::BTree(string str) {
createTree(root, str);
cout << "报告:创建一颗二叉树,完成!!!" << endl;
}
template<class T>
void BTree<T>::createTree(BTreeNode<T>*& bt, string str) {
static int i = 0;
char ch = ' ';
ch = str[i++];
if (ch == '#') bt = nullptr;
else {
bt = new BTreeNode<T>(ch);
createTree(bt->left, str);
createTree(bt->right, str);
}
};
// 判二叉树空否?
template<class T>
bool BTree<T>::IsEmpty() {
return (root == nullptr) ? true : false;
}
// 计算结点个数
template<class T>
int BTree<T>::Size(BTreeNode<T>* cur) {
if (cur == nullptr)
return 0;
else
return 1 + Size(cur->left) + Size(cur->right);
}
// 获取结点个数
template<class T>
int BTree<T>::getSize() {
return Size(root);
}
// 取得结点数据
template<class T>
BTreeNode<T>* BTree<T>::getData(T& item, BTreeNode<T>* cur) {
if (cur == nullptr) return nullptr;
if (cur->data == item) return cur;
return getData(item, cur->left) != nullptr ? getData(item, cur->left) : getData(item, cur->right);
}
// 判断item是否在树中
template<class T>
bool BTree<T>::Find(T& item) {
if (this->getData(item, root) == nullptr) return false;
else return true;
}
// 求树高度
template<class T>
int BTree<T>::Height(BTreeNode<T>* bt) {
if (bt == nullptr) return 0;
else {
int leftH = Height(bt->left);
int rightH = Height(bt->right);
return (leftH > rightH) ? leftH + 1 : rightH + 1;
}
}
// 获取树高度
template<class T>
int BTree<T>::getHeight() {
return Height(root);
}
// 获取根
template<class T>
BTreeNode<T>* BTree<T>::getRoot() {
if (!root) return nullptr;
else {
return this->root;
}
}
// 析构函数
template<class T>
BTree<T>::~BTree<T>() {
//cout << "调用析构函数" << endl;
destroyTree(root);
cout << "报告,这棵树已经销毁完毕!!!" << endl;
}
// 销毁二叉树
template<class T>
void BTree<T>::destroyTree(BTreeNode<T>* bt) {
// 后序遍历删除根为subTree的子树;
if (bt != nullptr) {
destroyTree(bt->left); //删除左子树
destroyTree(bt->right); //删除右子树
delete bt; //删除根结点
}
}
// 前序遍历
template<class T>
void BTree<T>::preOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
vec.push_back(cur->data); // 中
preOrderTraversal(cur->left, vec); // 左
preOrderTraversal(cur->right, vec); // 右
}
// 调用前序遍历,返回vector
template<class T>
vector<T> BTree<T>::preOrder() {
cout << "获取前序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
preOrderTraversal(root, resVec);
return resVec;
}
// 中序遍历
template<class T>
void BTree<T>::inOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
inOrderTraversal(cur->left, vec); // 左
vec.push_back(cur->data); // 中
inOrderTraversal(cur->right, vec); // 右
}
// 调用中序遍历,返回vector
template<class T>
vector<T> BTree<T>::inOrder() {
cout << "获取中序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
inOrderTraversal(root, resVec);
return resVec;
}
// 后序遍历
template<class T>
void BTree<T>::postOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr)
return;
postOrderTraversal(cur->left, vec); // 左
postOrderTraversal(cur->right, vec); // 右
vec.push_back(cur->data); // 中
}
// 调用后序遍历,返回vector
template<class T>
vector<T> BTree<T>::postOrder() {
cout << "获取后序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
postOrderTraversal(root, resVec);
return resVec;
}
// 层序遍历
template<class T>
void BTree<T>::levelOrderTraversal(BTreeNode<T>* cur, vector<int>& vec) {
if (cur == nullptr) return;
queue<BTreeNode<T>*> Queue;
BTreeNode<T>* p;
Queue.push(cur); // 根结点入队列
while (!Queue.empty()) {
p = Queue.front();
//cout << p->data << " ";//输出出队结点的数据
vec.push_back(p->data);
Queue.pop();
if (p->left != nullptr) {
Queue.push(p->left);
}
if (p->right != nullptr) {
Queue.push(p->right);
}
}
}
// 调用层序遍历,返回vector
template<class T>
vector<T> BTree<T>::levelOrder() {
cout << "获取层序遍历数组...." << endl;
cout << ">>>>";
vector<T> resVec;
levelOrderTraversal(root, resVec);
return resVec;
}
template<class T>
void BTree<T>::CopyTree(BTreeNode<T>* root, BTreeNode<T>*& copyRoot) {
if (!root) {
copyRoot = nullptr;
}
else {
copyRoot = new BTreeNode<T>;
copyRoot->data = root->data; //复制根节点
CopyTree(root->left, copyRoot->left); //递归复制左子树
CopyTree(root->right, copyRoot->right);//递归复制左子树
}
}
template<class T>
void BTree<T>::Copy(BTreeNode<T>*& copyRoot) {
CopyTree(root, copyRoot);
}
template<class T>
void BTree<T>::destroyCopyTree(BTreeNode<T>*& copyRoot) {
destroyTree(copyRoot);
cout << "报告,复制二叉树已销毁完毕!!!" << endl;
}
template<class T>
BTreeNode<T>* BTree<T>::FindParent(BTreeNode<T>* root, BTreeNode<T>* node) {
if (root == nullptr) return nullptr;
if (root->left == node || root->right == node)
return root; //找到, 返回父结点地址
BTreeNode <T>* p;
if ((p = FindParent(root->left, node)) != nullptr)
return p; //递归在左子树中搜索
else return FindParent(root->right, node);
}
test.cpp
#include "btree.h"
#include "btree.cpp"
//#include <iostream>
//using namespace std;
int main() {
cout << "-------------------------Start--------------------------" << endl;
cout << "---------------------创建原始二叉树---------------------" << endl;
string str = "ABD#G##E##CF###";
BTree<int>* T = new BTree<int>(str);
BTreeNode<int>* root = T->getRoot();
cout << "这棵树有 " << T->getSize() << " 个结点" << endl;
int zifu = 'G';
if (T->Find(zifu)) {
cout << "这棵树有 " << (char)zifu << " 结点" << endl;
}
else {
cout << "这棵树无 " << (char)zifu << " 结点" << endl;
}
BTreeNode<int>* node = T->getData(zifu, root);
if (node) {
cout << (char)node->data << endl;
BTreeNode<int>* nodeParent = T->FindParent(root, node);
if (!nodeParent) {
cout << "找不到父亲结点" << endl;
}
else {
cout << "结点 " << (char)zifu << " 的父亲结点是: " << (char)nodeParent->data << " 结点" << endl;
if (nodeParent->left) cout << "我的左孩子是: " << (char)nodeParent->left->data << endl;
else cout << "我没有左孩子..." << endl;
if (nodeParent->right) cout << "我的右孩子是: " << (char)nodeParent->right->data << endl;
else cout << "我没有右孩子..." << endl;
}
}
cout << "这棵树的高度为: " << T->getHeight() << endl;
vector<int> vec = T->preOrder();
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
vec = T->inOrder();
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
vec = T->postOrder();
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
vec = T->levelOrder();
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
cout << "-----------------------复制二叉树-----------------------" << endl;
// 复制二叉树
//vector<int> vec;
//BTreeNode<int>* root = T->getRoot();
BTreeNode<int>* copyRoot = new BTreeNode<int>;
//T->Copy(copyRoot); // 方法一
T->CopyTree(root, copyRoot); // 方法二
vec.clear();
cout << "获取前序遍历数组...." << endl;
cout << ">>>>";
T->preOrderTraversal(copyRoot, vec);
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
cout << "获取中序遍历数组...." << endl;
cout << ">>>>";
T->inOrderTraversal(copyRoot, vec);
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
cout << "获取后序遍历数组...." << endl;
cout << ">>>>";
T->postOrderTraversal(copyRoot, vec);
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
vec.clear();
cout << "获取层序遍历数组...." << endl;
cout << ">>>>";
T->levelOrderTraversal(copyRoot, vec);
for (auto i : vec) {
cout << (char)i;
}
cout << endl;
cout << "---------------------销毁复制二叉树---------------------" << endl;
T->destroyCopyTree(copyRoot);
cout << "---------------------销毁原始二叉树---------------------" << endl;
T->~BTree();
cout << "--------------------------End---------------------------" << endl;
return 0;
}
>>测试结果
-------------------------Start--------------------------
---------------------创建原始二叉树---------------------
报告:创建一颗二叉树,完成!!!
这棵树有 7 个结点
这棵树有 G 结点
G
结点 G 的父亲结点是: D 结点
我没有左孩子...
我的右孩子是: G
这棵树的高度为: 4
获取前序遍历数组....
>>>>ABDGECF
获取中序遍历数组....
>>>>DGBEAFC
获取后序遍历数组....
>>>>GDEBFCA
获取层序遍历数组....
>>>>ABCDEFG
-----------------------复制二叉树-----------------------
获取前序遍历数组....
>>>>ABDGECF
获取中序遍历数组....
>>>>DGBEAFC
获取后序遍历数组....
>>>>GDEBFCA
获取层序遍历数组....
>>>>ABCDEFG
---------------------销毁复制二叉树---------------------
报告,复制二叉树已销毁完毕!!!
---------------------销毁原始二叉树---------------------
报告,这棵树已经销毁完毕!!!
--------------------------End---------------------------