二叉树的总结

//BTNode.h

#ifndef BTNODE_H#define BTNODE_H#include <cstdio>typedef int datatype;typedef struct BTNode{           //定义节点datatype data;BTNode* left;BTNode* right;BTNode(datatype dataPara):data(dataPara),left(NULL),right(NULL){};}*nodePtr;#endif

//BT.h

#pragma once         #ifndef BT_H#define BT_H#include "BTNode.h"#include <iostream>#include <queue>using namespace std;class BT{public:BT():rootPtr(new BTNode(1)){ };~BT();//void addNode(datatype dataPara); //build a BT//void delNode(datatype dataPara);void preBuild(nodePtr &root); //C++在子函数中对指针赋值时，形参一定要传递指针的引用void allBuild();//层次建立一个二叉树，这是华为机试的一道题，挺有意思的void initBT();//真正建立二叉树的函数，可以调用上面的preBuild或allBuildvoid reverse();//真正遍历二叉树的函数，可以调用以下四种遍历方式void preRevHelp(nodePtr &node);void inRevHelp(nodePtr &node);void allRevHelp(nodePtr &node);//层次遍历void postRevHelp(nodePtr &node);int depthHelp(nodePtr &node);//求节点深度，形参是节点的指针void  queryDepthHelp(datatype val, nodePtr &node);//这也是一个递归函数，调用了上面的depthHelp，形参有一个node是为了方便递归int queryDepth(datatype val);//输入一个节点所保存的数据，查找并求深度，实际上调用了上面的Help，查找的过程用了遍历，找到了val则调用depthHelpnodePtr rootPtr;//一个空节点，rootPtr->left才是二叉树真正的根节点private:int depth;//用来保存查到的深度值};#endif

//BT.cpp

#include "BT.h"BT::~BT(){}void BT::preBuild(nodePtr &node)//前序遍历{datatype data;cin >> data;if (data == -1)node = NULL;else{node = new BTNode(data);preBuild(node->left);preBuild(node->right);}}void BT::initBT(){//preBuild(rootPtr->left);allBuild(); }void BT::preRevHelp(nodePtr &node){if (node != NULL){cout << node->data;preRevHelp(node->left);preRevHelp(node->right);}}void BT::reverse(){cout << "这是先序遍历的结果：" << endl;preRevHelp(rootPtr->left);cout << endl<< "这是中序遍历的结果：" << endl;inRevHelp(rootPtr->left);cout << endl<< "这是后序遍历的结果：" << endl;postRevHelp(rootPtr->left);cout << endl<<"这是层次遍历的结果：" << endl;allRevHelp(rootPtr->left);}void BT::inRevHelp(nodePtr &node){if (node != NULL){inRevHelp(node->left);cout << node->data <<" ";inRevHelp(node->right);}}void BT::postRevHelp(nodePtr &node){if (node != NULL){postRevHelp(node->left);postRevHelp(node->right);cout << node->data << " ";}}void BT::allRevHelp(nodePtr &node){vector <nodePtr> curr;vector <nodePtr> temp;curr.push_back(node);while (!curr.empty()){for (vector <nodePtr>::const_iterator i = curr.begin(); i != curr.end(); ++i){cout << (*i)->data << " ";if ((*i)->left)temp.push_back((*i)->left);if ((*i)->right)temp.push_back((*i)->right);}curr = temp;temp.clear();}}int BT::depthHelp(nodePtr &node){if (node == NULL)return 0;elsereturn max(depthHelp(node->left), depthHelp(node->right)) + 1;}void BT::allBuild() //层次建树就不要用递归了{vector <nodePtr> pre;vector <nodePtr> curr;//nodePtr child;//这个指针用来更新树中的父子节点关系int preIndex = 0;int currIndex = 0;int currLayer = 1; //这里配合题目需要，把顶层的序号设为1int value;int layer;pre.push_back(rootPtr); //先把最顶层的节点给推进来while (cin >> value >> layer){nodePtr node = new BTNode(value);if (layer != currLayer){currLayer = layer;pre = curr; //更新容器curr.clear();currIndex = preIndex = 0;}curr.push_back(node);if (!currIndex % 2)pre[preIndex]->left = node;else{pre[preIndex]->right = node;++preIndex;}++currIndex;}cin.clear();}void BT::queryDepthHelp(datatype val, nodePtr &node)//这里模仿先序遍历去查找一个值{if (node != NULL){if (node->data == val) depth =  depthHelp(node);//找到了就调用depthHelp去找他的深度queryDepthHelp(val, node->left);queryDepthHelp(val, node->right);}//没找到就输出-1}int BT::queryDepth(datatype val){depth = -1;queryDepthHelp(val, rootPtr->left);return depth;}

//Main.cpp

<pre class="cpp" name="code">#include "BT.h"int main(){BT A;A.initBT();//cout << A.rootPtr->data;A.reverse();cout << "节点3的深度为" << A.queryDepth(3) << endl;//system("pasue");return 0;}

先贴上代码，有时间再详解。老规矩：先挖坑，有空更。