cpp
复制代码
namespace key{
template<class k>
struct BSTreeNode
{
BSTreeNode<k>* _left;
BSTreeNode<k>* _right;
k _key;
BSTreeNode(const k& key)
:_left(nullptr)
,_right(nullptr)
,_key(key)
{}
};
template <class k>
class BSTree {
typedef BSTreeNode<k> Node;
private:
Node* _root = nullptr;
public:
BSTree() = default;
BSTree(const BSTree<k>& t) {
_root = Copy(t._root);
}
BSTree<k>& operator=(BSTree<k>& t) {
swap(_root, t._root);
return *this;
}
~BSTree() {
Destroy(_root);
}
bool FindR(const k& key) {
return _FindR(_root, key);
}
bool InsertR(const k& key) {
return _InsertR(_root, key);
}
bool EraseR(const k& key) {
return _EraseR(_root, key);
}
bool Insert(const k& key) {
if (_root == nullptr) {
_root = new BSTreeNode<k>(key);
return true;
}
Node* parent = nullptr;
Node* cur = _root;
while (cur) {
if (cur->_key < key) {
parent = cur;
cur = cur->_right;
}
else if (cur->_key > key) {
parent = cur;
cur = cur->_left;
}
else {
return false;
}
}
cur = new BSTreeNode<k>(key);
if (cur->_key > parent->_key) {
parent->_right = cur;
}
else if (cur->_key < parent->_key) {
parent->_left = cur;
}
return true;
}
bool find(const k& key) {
Node* cur = _root;
while (cur)
{
if (cur->_key < key) {
cur = cur->_right;
}
else if (cur->_key > key) {
cur = cur->_left;
}
else {
return true;
}
}
return false;
}
bool Erase(const k& key) {
Node* parent = nullptr;
Node* cur = _root;
while (cur)
{
if (cur->_key < key) {
parent = cur;
cur = cur->_right;
}
else if (cur->_key > key) {
parent = cur;
cur = cur->_left;
}
else
{
//1.左为空
if (cur->_left == nullptr) {
if (cur == _root) {
_root = cur->_right;
}
else if (parent->_left == cur) {
parent->_left = cur->_right;
}
else {
parent->_right = cur->_right;
}
delete cur;
}
//2.右为空
else if (cur->_right == nullptr)
{
if (cur == _root) {
_root = cur->_left;
}
else if (parent->_left == cur) {
parent->_left = cur->_left;
}
else {
parent->_right = cur->_left;
}
delete cur;
}
//3.左右都不为空
else
{
//找右树最小节点替代,也可以是左树最大节点替代(这里找的右树的最小结点)
Node* pminright = cur; //preminright
Node* minright = cur->_right;
while (minright->_left) {
pminright = minright;
minright = minright->_left;
}
cur->_key = minright->_key;
if (pminright->_left == minright) {
//minright的最小节点没有左子树且为pminright的左孩子
pminright->_left = minright->_right;
}
else
{
//minright的最小节点没有左子树且为pminright的右孩子
pminright->_right = minright->_right;
}
delete minright;
}
return true;
}
}
return false;
}
void InOrder() {
_InOrder(_root);
cout << endl;
}
void _InOrder(Node* root) {
if (root == nullptr) {
return;
}
_InOrder(root->_left);
cout << root->_key << " ";
_InOrder(root->_right);
}
protected:
Node* Copy(Node* _root) {
if (_root == nullptr)
return nullptr;
Node* newRoot = new Node(_root->_key);
newRoot->_left = Copy(_root->_left);
newRoot->_right = Copy(_root->_right);
return newRoot;
}
void Destroy(Node* root) {
if (root == nullptr) {
return;
}
Destroy(root->_left);
Destroy(root->_right);
delete root;
root = nullptr;
}
bool _FindR(Node* root,const k& key) {
if (root == nullptr)
return false;
if (root->_key == key) {
return true;
}
if (root->_key > key) {
return _FindR(root->_left, key);
}
else
{
return _FindR(root->_right, key);
}
}
bool _InsertR(Node*& root, const k& key) {
if (root == nullptr) {
root = new Node(key);
return true;
}
if (root->_key < key)
{
return _InsertR(root->_right, key);
}
else if (root->_key > key)
{
return _InsertR(root->_left, key);
}
else
{
return false;
}
}
bool _EraseR(Node*& root, const k& key) {
if (root == nullptr)
return false;
if (root->_key < key)
{
return _EraseR(root->_right, key);
}
else if (root->_key > key)
{
return _EraseR(root->_left, key);
}
else
{
Node* del = root;
// 开始准备删除
if (root->_right == nullptr)
{
root = root->_left;
}
else if (root->_left == nullptr)
{
root = root->_right;
}
else
{
Node* maxleft = root->_left;
while (maxleft->_right)
{
maxleft = maxleft->_right;
}
swap(root->_key, maxleft->_key);
return _EraseR(root->_left, key);
}
delete del;
return true;
}
}
};
};
cpp
复制代码
namespace key_value
{
template<class K, class V>
struct BSTreeNode
{
BSTreeNode<K, V>* _left;
BSTreeNode<K, V>* _right;
K _key;
V _value;
BSTreeNode(const K& key, const V& value)
:_left(nullptr)
, _right(nullptr)
, _key(key)
, _value(value)
{}
};
template<class K, class V>
class BSTree
{
typedef BSTreeNode<K, V> Node;
public:
bool Insert(const K& key, const V& value)
{
if (_root == nullptr)
{
_root = new Node(key, value);
return true;
}
Node* parent = nullptr;
Node* cur = _root;
while (cur)
{
if (cur->_key < key)
{
parent = cur;
cur = cur->_right;
}
else if (cur->_key > key)
{
parent = cur;
cur = cur->_left;
}
else
{
return false;
}
}
cur = new Node(key, value);
// 链接
if (parent->_key < key)
{
parent->_right = cur;
}
else
{
parent->_left = cur;
}
return true;
}
Node* Find(const K& key)
{
Node* cur = _root;
while (cur)
{
if (cur->_key < key)
{
cur = cur->_right;
}
else if (cur->_key > key)
{
cur = cur->_left;
}
else
{
return cur;
}
}
return nullptr;
}
bool Erase(const K& key)
{
Node* parent = nullptr;
Node* cur = _root;
while (cur)
{
if (cur->_key < key)
{
parent = cur;
cur = cur->_right;
}
else if (cur->_key > key)
{
parent = cur;
cur = cur->_left;
}
else
{
// 删除
// 1、左为空
if (cur->_left == nullptr)
{
if (cur == _root)
{
_root = cur->_right;
}
else
{
if (parent->_left == cur)
{
parent->_left = cur->_right;
}
else
{
parent->_right = cur->_right;
}
}
delete cur;
} // 2、右为空
else if (cur->_right == nullptr)
{
if (cur == _root)
{
_root = cur->_left;
}
else
{
if (parent->_left == cur)
{
parent->_left = cur->_left;
}
else
{
parent->_right = cur->_left;
}
}
delete cur;
}
else
{
// 找右树最小节点替代,也可以是左树最大节点替代
Node* pminRight = cur;
Node* minRight = cur->_right;
while (minRight->_left)
{
pminRight = minRight;
minRight = minRight->_left;
}
cur->_key = minRight->_key;
if (pminRight->_left == minRight)
{
pminRight->_left = minRight->_right;
}
else
{
pminRight->_right = minRight->_right;
}
delete minRight;
}
return true;
}
}
return false;
}
void InOrder()
{
_InOrder(_root);
cout << endl;
}
protected:
void _InOrder(Node* root)
{
if (root == nullptr)
return;
_InOrder(root->_left);
cout << root->_key << ":" << root->_value << endl;
_InOrder(root->_right);
}
private:
Node* _root = nullptr;
};
}
cpp
复制代码
#include<iostream>
#include"BSTree.h"
using namespace std;
void TestBSTree()
{
int a[] = { 8, 3, 1, 10, 6, 4, 7, 14, 13 };
key::BSTree<int> t1;
for (auto e : a)
{
t1.Insert(e);
}
t1.InOrder();
t1.Erase(4);
t1.InOrder();
t1.Erase(14);
t1.InOrder();
t1.Erase(3);
t1.InOrder();
t1.Erase(8);
t1.InOrder();
for (auto e : a)
{
cout << "delete:" << e << " ";
t1.Erase(e);
t1.InOrder();
}
t1.InOrder();
}
void TestBSTree2()
{
int a[] = { 8, 3, 1, 10, 6, 4, 7, 14, 13 };
key::BSTree<int> t1;
for (auto e : a)
{
t1.InsertR(e);
}
t1.InOrder();
t1.EraseR(10);
t1.EraseR(14);
t1.EraseR(13);
t1.InOrder();
for (auto e : a)
{
t1.EraseR(e);
t1.InOrder();
}
t1.InOrder();
}
void TestBSTree3()
{
int a[] = { 8, 3, 1, 10, 6, 4, 7, 14, 13 };
key::BSTree<int> t1;
for (auto e : a)
{
t1.InsertR(e);
}
t1.InOrder();
key::BSTree<int> t2(t1);
t2.InOrder();
}
void TestBSTree4()
{
key_value::BSTree<string, string> dict;
dict.Insert("sort", "排序");
dict.Insert("left", "左边");
dict.Insert("right", "右边");
dict.Insert("string", "字符串");
dict.Insert("insert", "插入");
dict.Insert("erase", "删除");
string str;
while (cin >> str)
{
auto ret = dict.Find(str);
if (ret)
{
cout << ":" << ret->_value << endl;
}
else
{
cout << "无此单词" << endl;
}
}
}
void TestBSTree5()
{
string arr[] = { "西瓜", "西瓜", "苹果", "西瓜", "苹果", "苹果", "西瓜", "苹果", "香蕉", "苹果", "香蕉", "梨" };
key_value::BSTree<string, int> countTree;
for (auto str : arr)
{
//key_value::BSTreeNode<string, int>* ret = countTree.Find(str);
auto ret = countTree.Find(str);
if (ret == nullptr)
{
countTree.Insert(str, 1);
}
else
{
ret->_value++;
}
}
countTree.InOrder();
}
int main()
{
TestBSTree();
cout << "1" << endl;
TestBSTree2();
cout << "2" << endl;
TestBSTree3();
cout << "3" << endl;
//TestBSTree4();
cout << "4" << endl;
TestBSTree5();
cout << "5" << endl;
return 0;
}