红黑树实现

闲来无事,自己实现一个红黑树玩玩,顺便加深一下红黑树的理解
实现了红黑树的构造操作,删除节点留待日后更新
贴上代码:

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//
// main.cpp
// RBTree
//
// Created by apple on 14-11-23.
// Copyright (c) 2014年 apple. All rights reserved.
//

#include <iostream>

using namespace std;

struct Node
{
Node* pLeft;
Node* pRight;
Node* pParent;
int32_t iValue;
bool bRed;
void print(){
cout<<(bRed ? "R" : "B")<<iValue;
};
};

Node* root = NULL;
int32_t size = 0;

void LRotate(Node* node)
{
if (NULL == node->pRight)
{
return;
}
// node是根节点
if (NULL == node->pParent)
{
root = node->pRight;
root->pParent = NULL;

node->pParent = root;
node->pRight = root->pLeft;
root->pLeft = node;
if (node->pRight != NULL)
{
node->pRight->pParent = node;
}
return;
}

// node是内部节点
node->pRight->pParent = node->pParent;
if (node->pParent->pLeft == node)
{
node->pParent->pLeft = node->pRight;
}
else
{
node->pParent->pRight = node->pRight;
}
node->pParent = node->pRight;
node->pRight = node->pParent->pLeft;
node->pParent->pLeft = node;
if (node ->pRight != NULL)
{
node->pRight->pParent = node;
}
}

void RRotate(Node* node)
{
if (NULL == node->pLeft)
{
return;
}
// node是根节点
if (NULL == node->pParent)
{
root = node->pLeft;
root->pParent = NULL;

node->pParent = root;
node->pLeft = root->pRight;
root->pRight = node;
if (node->pLeft != NULL)
{
node->pLeft->pParent = node;
}
return;
}

// node是内部节点
node->pLeft->pParent = node->pParent;
if (node->pParent->pRight == node)
{
node->pParent->pRight = node->pLeft;
}
else
{
node->pParent->pLeft = node->pLeft;
}
node->pParent = node->pLeft;
node->pLeft = node->pParent->pRight;
node->pParent->pRight = node;
if (node ->pLeft != NULL)
{
node->pLeft->pParent = node;
}
}

void adjust(Node* node)
{
if (node == NULL)
{
return;
}
if (node->pParent == NULL)
{
// node是根节点
node->bRed = false;
return;
}

// 1.如果插入节点的父节点是黑色的,无需调整
if (node->pParent->bRed == false)
{
return;
}
// 2.插入节点的叔叔节点是红色的
// 插入节点变黑色,父亲叔叔变红色,祖父变红色,对祖父作调整
if (node->pParent->pParent->pLeft != NULL && node->pParent->pParent->pLeft->bRed &&
node->pParent->pParent->pRight != NULL && node->pParent->pParent->pRight->bRed)
{
node->pParent->pParent->pLeft->bRed = false;
node->pParent->pParent->pRight->bRed = false;
node->pParent->pParent->bRed = true;
adjust(node->pParent->pParent);
return;
}
// 3.插入节点的叔叔节点是黑色的,父节点红色
if (node->pParent->pParent->pLeft == node->pParent && node->pParent->pLeft == node)
{
// 变色,再对祖父节点作右旋
node->pParent->bRed = false;
node->pParent->pParent->bRed = true;
RRotate(node->pParent->pParent);
}
else if (node->pParent->pParent->pRight == node->pParent && node->pParent->pRight == node)
{
node->pParent->bRed = false;
node->pParent->pParent->bRed = true;
LRotate(node->pParent->pParent);
}
else if(node->pParent->pParent->pLeft == node->pParent && node->pParent->pRight == node)
{
LRotate(node->pParent);
adjust(node);
}
else
{
RRotate(node->pParent);
adjust(node);
}
}

void insert(int32_t value, Node* node)
{
if (node == NULL)
{
// 根节点
root = new Node();
root->bRed = false;
root->iValue = value;
return;
}
// 插入
Node* pTemp;
if (node->iValue > value)
{
if (node->pLeft != NULL)
{
insert(value, node->pLeft);
}
else
{
node->pLeft = new Node();
pTemp = node->pLeft;
}
}
else
{
if (node->pRight != NULL)
{
insert(value, node->pRight);
}
else
{
node->pRight = new Node();
pTemp = node->pRight;
}
}

if (pTemp != NULL)
{
pTemp->pParent = node;
pTemp->iValue = value;
pTemp->bRed = true;
// 开始调整
adjust(pTemp);
pTemp = NULL;
}
}

void print_pre(Node* node)
{
if (NULL == node)
{
return;
}
node->print();
print_pre(node->pLeft);
print_pre(node->pRight);
}

void print_mid(Node* node)
{
if (NULL == node)
{
return;
}
print_mid(node->pLeft);
node->print();
print_mid(node->pRight);
}

int main(int argc, const char * argv[])
{
insert(1, root);
insert(2, root);
insert(3, root);
insert(4, root);
insert(5, root);
insert(6, root);
insert(7, root);
print_pre(root);
print_mid(root);
return 0;
}
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