数据结构——排序/搜索二叉树(递归)的基本操作实现

<strong><span style="font-size:18px;">#pragma once

template<class K,class V>
class BSTreeRNode
{
public:
K _key;
V _value;

BSTreeRNode<K,V>* _left;
BSTreeRNode<K,V>* _right;

BSTreeRNode(const K& key,const V& value)
:_key(key)
,_value(value)
,_left(NULL)
,_right(NULL)
{}
};

template<class K,class V>
class BSTreeR
{
typedef BSTreeRNode<K,V> Node;
public:
BSTreeR()
:_root(NULL)
{}
bool Insert(const K& key,const V& value)
{
return _Insert(_root,key,value);
}

Node* Find(const K& key)
{
return _Find(_root,key);
}

bool ReMove(const K& key)
{
return _ReMove(_root,key);
}

void IrOrder()
{
return _InOrder(_root);
}
private:
bool _ReMove(Node*& root,const K& key)//删除节点后变成一颗新的树，所以改变了树，要用引用
{
if (root == NULL)
{
return false;
}

if (root->_key > key)
{
_ReMove(root->_left,key);
}
else if (root->_key < key)
{
_ReMove(root->_right,key);
}
else//root->_key == key 找到了，下面进行删除工作
{
if (root->_left == NULL)
{
root = root->_right;
}
else if (root->_right == NULL)
{
root = root->_left;
}
else //root->_left != NULL && root->_right != NULL
{
Node* parent = root;
Node* subRight = root->_right;//subRight为删除节点的右孩子

while (subRight->_left)//寻找删除节点右孩子的最左节点
{
parent = subRight;
subRight = subRight->_left;
}

root->_key = subRight->_key;
root->_value = subRight->_value;

if (parent->_left == subRight)
{
parent->_left = subRight->_right;
}
else //parent->_right == subRight
{
parent->_right = subRight->_right;
}

delete subRight;
return true;
}
}
return false;
}

Node* _Find(Node* root,const K& key)
{
if (root == NULL)
{
return NULL;
}

if (root->_key > key)
{
_Find(root->_left,key);
}
else if (root->_key < key)
{
_Find(root->_right,key);
}
else
{
return root;
}
}

void _InOrder(Node* root)
{
if (root == NULL)
{
return;
}

_InOrder(root->_left);
cout<<root->_key<<" ";
_InOrder(root->_right);
}

bool _Insert(Node*& root,const K& key,const V& value)//这里要传root的引用，因为在函数调用中要修改root的值
{
if (root == NULL)
{
root = new Node(key,value);
return true;
}

if (root->_key > key)
{
_Insert(root->_left,key,value);//刚开始写的时候前面没有加return，错误
}
else if (root->_key < key)
{
_Insert(root->_right,key,value);
}
else //root->_key == key
{
return false;
}
}
private:
Node* _root;
};

</span></strong>

<strong><span style="font-size:18px;">#define _CRT_SECURE_NO_WARNINGS 1

#include <iostream>
using namespace std;
#include "BSTreeR.h"

void TestBSTreeR()
{
BSTreeR<int,int> bsr;
int arr[] = {5,9,3,7,2,4,0,8,6,1};
int size = sizeof(arr)/sizeof(arr[0]);

for (int i = 0;i < size;i++)
{
bsr.Insert(arr[i],i+1);
}
bsr.IrOrder();
cout<<endl;

cout<<bsr.Find(6)->_key<<" "<<bsr.Find(6)->_value<<endl;

bsr.ReMove(5);
bsr.ReMove(9);
bsr.ReMove(1);
bsr.ReMove(55);
bsr.IrOrder();
cout<<endl;

bsr.ReMove(0);
bsr.ReMove(1);
bsr.ReMove(2);
bsr.ReMove(3);
bsr.ReMove(4);
bsr.ReMove(5);
bsr.ReMove(6);
bsr.ReMove(7);
bsr.ReMove(8);
bsr.ReMove(9);
bsr.IrOrder();
cout<<endl;
}

int main()
{
TestBSTreeR();
system("pause");
return 0;
}</span></strong>