// Demo2.cpp : 定义控制台应用程序的入口点。
//

#include "stdafx.h"

#include <iostream>
using namespace std;
#define max(a,b) ((a)>(b)?(a):(b))


typedef struct AVLtree
{
	struct AVLtree * left,*right,*parent;
	int hight;
	int data;
}AVLTree,*PAVLTree;


PAVLTree rightleft(PAVLTree p);
PAVLTree leftright(PAVLTree p);
PAVLTree rightright(PAVLTree p);
PAVLTree leftleft(PAVLTree p);
PAVLTree insert(int x,PAVLTree p);
PAVLTree find(int data,PAVLTree p);
PAVLTree avl_delete(int data,PAVLTree p);
PAVLTree findMin(PAVLTree p);
PAVLTree findMax(PAVLTree p);
int Height(PAVLTree p);

PAVLTree findMin(PAVLTree p)
{
	while(p && p->left)
	{
		p = p->left;
	}
	return p;
}
PAVLTree findMax(PAVLTree p)
{

	while(p && p->right)
	{
		p = p->right;
	}
	return p;
}

//删除节点可能会导致根节点的改变，所以必须返回根节点,以利于后面的操作
PAVLTree avl_delete(int data,PAVLTree p)
{
	if(!p) return NULL;
	while(1)
	{
		if(data > p->data)
		{
			p=p->right;
			if( (Height(p->right)-Height(p->left)) ==2 )
			{
				if(data<p->right->data)
				{
					p=rightleft(p);
				}else
				{
					p=rightright(p);
				}
			}
		}else if( data < p->data )
		{	
			p=p->left;
			if( (Height(p->left)-Height(p->right)) ==2 )
			{
				if(data >  (p->left->data) )
				{
					p=leftright(p);
				}else
				{
					p=leftleft(p);
				}
			}
		}else if(p->left && p->right)
		{
			PAVLTree t = findMin(p->right);
			p->data = t->data;
			
			data=t->data;
			p=p->right;
		}else
		{
			PAVLTree t = p->parent;
			
			if(t->left && t->left->data == data)
			{
				t->left=NULL;
			}else if(t->right &&  t->right->data==data)
			{
				t->right = p->right;
			}
			p->left=p->right=NULL;
			free(p);
			p=NULL;
			p=t;
			break;
		}
		if(p)
			p->hight = max(Height(p->left),Height(p->right))+1;
	}
	
	while(p)
	{
		p->hight = max(Height(p->left),Height(p->right))+1;

		if( (Height(p->left)-Height(p->right)) ==2 )
		{
			if(p->left->left->hight < p->left->right->hight)
			{
				p =leftright(p);
			}else
			{
				p=leftleft(p);
			}
		}

		if( (Height(p->right)-Height(p->left)) ==2 )
		{
			if(p->right->left->hight>p->right->right->hight)
			{
				p=rightleft(p);
			}else
			{
				p=rightright(p);
			}
		}
		if(p->parent)
			p=p->parent;
		else break;
	}
	return p;
}


PAVLTree find(int data,PAVLTree p)
{
	while(p)
	{
		if(data >p->data)
			p = p->right;
		else if(data < p->data)
			p = p->left;
		else
			return p;
	}

	return NULL;
}

int Height(PAVLTree p)
{
	if(p==NULL)
		return -1;
	else
		return p->hight;
}
PAVLTree leftright(PAVLTree p)
{
	PAVLTree tmp=rightright(p->left);
	p->left=tmp;
	tmp->parent=p;
	return leftleft(p);

}
PAVLTree leftleft(PAVLTree p)
{ 
	PAVLTree t = p->left;

	p->left =t->right;
	if(p->left)
		p->left->parent=p;
	p->parent=t;
	t->right=p;
	t->parent=NULL;

	p->hight = max(Height(p->left),Height(p->right))+1;
	t->hight = max(Height(t->left),Height(t->right))+1;

	return t;
}//=====================================================================================================

PAVLTree rightleft(PAVLTree p)
{
	PAVLTree tmp= leftleft(p->right);
	p->right = tmp;
	tmp->parent=p;
	return rightright(p);
}

PAVLTree rightright(PAVLTree p)
{
	PAVLTree t= p->right;
	p->right=t->left;
	if(p->right)
		p->right->parent=p;
	p->parent=t;

	t->left=p;
	t->parent=NULL;

	p->hight = max(Height(p->left),Height(p->right))+1;
	t->hight = max(Height(t->left),Height(t->right))+1;

	return t;
}

PAVLTree insert(int x,PAVLTree p)
{
	if(p==NULL)
	{
		p = (PAVLTree)malloc(sizeof(AVLTree));
		if(p==NULL)
		{
			return NULL;
		}else
		{
			p->data=x;
			p->left=p->right=p->parent=NULL;
			p->hight=0;
		}
	}else if(x < p->data )
	{
		p->left=insert(x,p->left); // 80   
		p->left->parent = p;
		if( (Height(p->left)-Height(p->right)) ==2 )
		{
			if(x >  (p->left->data) )
			{
				p=leftright(p);
			}else
			{
				p=leftleft(p);
			}
		}
	}else if(x > p->data)
	{
		//返回的值是为了计算深度
		p->right = insert(x,p->right);
		p->right->parent =p;
		if( (Height(p->right)-Height(p->left)) ==2 )
		{
			if(x<p->right->data)
			{
				p=rightleft(p);
			}else
			{
				p=rightright(p);
			}
		}
	}
	p->hight = max(Height(p->left),Height(p->right))+1;

	return p;
}

void print_tree(PAVLTree t)
{
	if(t)
	{
		cout<<t->data<<" ";
		print_tree(t->left);
		print_tree(t->right);
	}
}



int _tmain(int argc, _TCHAR* argv[])
{
	AVLTree *pt=NULL;
/*
	pt=insert(100,pt);
	pt=insert(80,pt);
	pt=insert(110,pt);
	pt=insert(70,pt);
	pt=insert(85,pt);
	pt=insert(60,pt);
	*/

	//测试左右旋转
/*
	pt=insert(120,pt);
	pt=insert(110,pt);
	pt=insert(150,pt);
	pt=insert(70,pt);
	pt=insert(111,pt);
	pt=insert(115,pt);
	*/

	pt=insert(150,pt);
	pt=insert(130,pt);
	pt=insert(180,pt);
	pt=insert(170,pt);
	pt=insert(200,pt);
	pt=insert(160,pt);
	pt=insert(161,pt);
	pt=insert(162,pt);
	pt=insert(165,pt);

	print_tree(pt);
	cout<<endl;
	cout<<find(180,pt)->data<<endl;
	cout<<"Max = "<<findMax(pt)->data<<endl;
	cout<<"Min = "<<findMin(pt)->data<<endl;
	pt=avl_delete(161,pt);
	cout<<" After del 161"<<endl;
	print_tree(pt);
	pt=avl_delete(200,pt);
	pt=avl_delete(162,pt);
	cout<<endl;
	cout<<" After del 200"<<endl;
	print_tree(pt);

	getchar();
	return 0;
}

细节后续完善…