* error:get_postnode reverse the sequence of right and left
* error: while ((p->data != it) && (p != NULL))
This commit is contained in:
Wenkai Zhou 2019-05-08 15:20:49 +00:00
parent 3b23b938e0
commit 622fb3a80a

View File

@ -1,40 +1,47 @@
/*
* Filename: /home/zwk/code/data_structrue/c++/tree/binary_search_tree/main.cpp
* Path: /home/zwk/code/data_structrue/c++/tree/binary_search_tree
* Created Date: Wednesday, May 8th 2019, 11:04:48 pm
* Author: zwk
*
* refer to https://time.geekbang.org/column/article/68334
*/
#include <iostream>
using namespace std;
typedef int DataType;
struct tree_node
struct treeNode
{
DataType data;
tree_node* left=NULL;
tree_node* right=NULL;
treeNode *left = nullptr;
treeNode *right = nullptr;
};
class binary_search_tree{
class binarySearchTree
{
private:
tree_node* root;
int num;
treeNode *root;
int num; // tree node numbers
public:
binary_search_tree() :num(0)
binarySearchTree() : num(0)
{
root = new tree_node;
root->left = NULL;
root->right = NULL;
root = new treeNode;
root->left = nullptr;
root->right = nullptr;
}
bool find(DataType it,tree_node* root)
bool find(DataType it, treeNode *root)
{
if (NULL == root)return false;
if (nullptr == root)
return false;
if (it == root->data) {
return true;
}
else if (it > root->data)
{
} else if (it > root->data) {
return find(it, root->right);
}
else
{
} else {
return find(it, root->left);
}
}
@ -43,8 +50,8 @@ public:
{
return find(it, root);
/*
tree_node* p = root;
while (p != NULL)
treeNode* p = root;
while (p != nullptr)
{
if (it < p->data)p = p->left;
else if (it>p->data)p = p->right;
@ -54,35 +61,49 @@ public:
*/
}
DataType get_max()
{
if (nullptr == root)
return NULL;
treeNode *tmp = root;
while (tmp->right != nullptr) {
tmp = tmp->right;
}
return tmp->data;
}
DataType get_min()
{
if (nullptr == root)
return NULL;
treeNode *tmp = root;
while (tmp->left != nullptr) {
tmp = tmp->left;
}
return tmp->data;
}
void insert_data(DataType it)
// 利用二分查找的思想,借助树的结构使用递归
{
if (0==num)
{
if (0 == num) {
root->data = it;
num++;
return;
}
tree_node* p = root;
while (p != NULL)
{
if (it < p->data)
{
if (NULL == p->left)
{
p->left = new tree_node;
treeNode *p = root;
while (p != nullptr) {
if (it < p->data) {
if (nullptr == p->left) {
p->left = new treeNode;
p->left->data = it;
num++;
return;
}
p = p->left;
}
else
{
if (NULL == p->right)
{
p->right = new tree_node;
} else {
if (nullptr == p->right) {
p->right = new treeNode;
p->right->data = it;
num++;
return;
@ -90,142 +111,79 @@ public:
p = p->right;
}
}
}
void delet(DataType it)
{
if (NULL == root)return;
tree_node* p = root;
tree_node* pp = NULL;//pp记录的是p的父节点
while (p != NULL&&p->data != it)
{
pp = p;
if (it > p->data)p = p->right;
else
p = p->left;
}
if (p == NULL)return;//没有找到
//删除的节点有两个子节点
if (p->left != NULL&&p->right != NULL)
{
tree_node* minP = p->right;
tree_node* minPP = p;//记录P的父节点
while (minP->left != NULL)//寻找右子树最小节点
{
minPP = minP;
minP = minP->left;
}
p->data = minP->data;//将minP替换到p中
//将p换到叶节点上使用叶节点方法进行删除
p = minP;
pp = minPP;
}
//删除节点是叶节点或者是仅有一个节点
tree_node* child;
if (p->left != NULL) child = p->left;
else if (p->right != NULL) child = p->right;
else child = NULL;
if (NULL == pp) root = child;//删除的是根节点
else if (p == pp->left)pp->left = child;
else pp->right = child;
}
DataType get_max()
{
if (NULL == root)return NULL;
tree_node* tmp=root;
while (tmp->right != NULL)
{
tmp = tmp->right;
}
return tmp->data;
}
DataType get_min()
{
if (NULL == root)return NULL;
tree_node* tmp=root;
while (tmp->left != NULL)
{
tmp = tmp->left;
}
return tmp->data;
}
DataType get_prenode(DataType it)
{
if (NULL == root)return NULL;
if (it == root->data) return NULL;
tree_node* p=root;
tree_node* pp=NULL;
while ((p->data != it)&&(p!=NULL))
{
pp = p;
if (p->data < it)
{
p=p->right;
}
else
{
if (nullptr == root)
return NULL;
if (it == root->data)
return NULL;
treeNode *p = root;
treeNode *pp = nullptr;
while (p != nullptr) {
if (p->data < it) {
pp = p; // label parent root
p = p->right;
} else if (p->data > it) {
pp = p; // label parent root
p = p->left;
} else {
break;
}
}
return ((NULL==p)?NULL:pp->data);
return ((nullptr == p) ? NULL : pp->data);
}
DataType get_postnode(DataType it)
{
if (NULL == root)return -1;
tree_node* p = root;
while ((p->data != it) && (p != NULL))
{
if (p->data < it)
{
p = p->left;
}
else
{
p = p->right;
}
}
if (NULL == p)
{
if (nullptr == root)
return -1;
treeNode *p = root;
while (p != nullptr) {
if (p->data < it) {
p = p->right;
} else if (p->data > it) {
p = p->left;
} else {
break;
}
else if (p->left!=NULL)
{
}
if (nullptr == p) {
return -1;
} else if (p->left != nullptr) {
return p->left->data;
}
else if (p->right!=-NULL)
{
} else if (p->right != nullptr) {
return p->right->data;
}
else
{
} else {
return NULL;
}
}
void mid_order(tree_node* rt)
void mid_order(treeNode *rt)
{
if (NULL == rt)return;
if (nullptr == rt)
return;
mid_order(rt->left);
cout << rt->data;
cout << rt->data << '\t';
mid_order(rt->right);
}
void order()
{
if (NULL == root)return;
if (nullptr == root)
return;
return mid_order(root);
}
int get_high(tree_node* rt)
int get_high(treeNode *rt)
{
int lhigh = 0;
int rhigh = 0;
if (NULL == rt)return 0;
if (nullptr == rt)
return 0;
lhigh = get_high(rt->left);
rhigh = get_high(rt->right);
return ((lhigh > rhigh) ? (lhigh + 1) : (rhigh + 1));
@ -233,35 +191,100 @@ public:
int high()
{
if (NULL == root) return 1;
if (nullptr == root)
return 1;
return get_high(root);
}
void delet(DataType it)
{
if (NULL == root)
return;
treeNode *p = root;
treeNode *pp = NULL; //pp记录的是p的父节点
while (p != NULL && p->data != it) {
pp = p;
if (it > p->data)
p = p->right;
else
p = p->left;
}
if (p == NULL)
return; //没有找到
//删除的节点有两个子节点
if (p->left != NULL && p->right != NULL) {
treeNode *minP = p->right;
treeNode *minPP = p; //记录P的父节点
while (minP->left != NULL) //寻找右子树最小节点
{
minPP = minP;
minP = minP->left;
}
// 注意这里,非常巧妙的办法。只是换值。“换汤不换药”
// 用后继节点替换到要删除节点的位置。 然后就变成删除后继节点的问题了。为了逻辑统一 代码书写简洁。我们把后继节点赋给了p
p->data = minP->data; //将minP的值替换到p中
//将p换到叶节点上使用叶节点方法进行删除 而且最小节点肯定没有左节点,叶节点删除方法参见后面的代码。
p = minP;
pp = minPP;
}
//删除节点是叶节点或者是仅有一个节点
treeNode *child;
if (p->left != NULL)
child = p->left;
else if (p->right != NULL)
child = p->right;
else
child = NULL;
if (NULL == pp)
root = child; //删除的是根节点
else if (p == pp->left)
pp->left = child;
else
pp->right = child;
}
};
int main()
{
binary_search_tree my_tree;
binarySearchTree my_tree;
my_tree.insert_data(5);
my_tree.insert_data(4);
my_tree.insert_data(6);
my_tree.insert_data(10);
my_tree.insert_data(3);
my_tree.insert_data(8);
my_tree.insert_data(1);
if (my_tree.find_data(3))
{
cout << "找到了数字3" << endl;
// must input in the order of layers
my_tree.insert_data(33);
my_tree.insert_data(16);
my_tree.insert_data(50);
my_tree.insert_data(13);
my_tree.insert_data(18);
my_tree.insert_data(34);
my_tree.insert_data(58);
my_tree.insert_data(15);
my_tree.insert_data(17);
my_tree.insert_data(25);
my_tree.insert_data(51);
my_tree.insert_data(66);
my_tree.insert_data(19);
my_tree.insert_data(27);
my_tree.insert_data(55);
if (my_tree.find_data(25)) {
cout << "找到了数字25" << endl;
} else {
cout << "没有找到数字25" << endl;
}
else
{
cout << "没有找到数字3" << endl;
}
my_tree.delet(4);
cout << "Max" << my_tree.get_max() << endl;
cout << "Min" << my_tree.get_min() << endl;
cout << "pre node of 5 is " <<my_tree.get_prenode(5) <<endl;
cout << "post node of 5 is " << my_tree.get_postnode(5) << endl;
my_tree.delet(13);
my_tree.delet(18);
my_tree.delet(55);
cout << "Max: " << my_tree.get_max() << endl;
cout << "Min: " << my_tree.get_min() << endl;
cout << "pre node of 17 is " << my_tree.get_prenode(17) << endl;
cout << "pre node of 51 is " << my_tree.get_prenode(51) << endl;
cout << "pre node of 33 is " << my_tree.get_prenode(33) << endl;
cout << "post node of 19 is " << my_tree.get_postnode(19) << endl;
cout << "post node of 25 is " << my_tree.get_postnode(25) << endl;
cout << "post node of 58 is " << my_tree.get_postnode(58) << endl;
cout << "post node of 58 is " << my_tree.get_postnode(51) << endl;
my_tree.order();
cout << "high of tree is " << my_tree.high() << endl;
return 0;