AVL C++實現(持續更新)

/*
 * =====================================================================================
 *
 *       Filename:  avl.cpp
 *
 *    Description:  AVL借鑑Mark Allen Weiss的《數據結構與算法分析C++描述》跟網上
 *		    一些大牛的模板寫的，寫的操作還比較簡單，後續有機會會添加更強
 *		    大的功能的～  
 *
 *        Version:  1.0
 *        Created:  2012年02月04日 21時41分02秒
 *       Revision:  none
 *       Compiler:  gcc
 *
 *         Author:  SphinX (Whisper), 
 *   Organization:  HFUT
 *
 * =====================================================================================
 */

#include <iostream>
#include <cstdlib>
#include <cstring>
using namespace std;

struct AvlNode
{
	int element;
	AvlNode * left;
	AvlNode * right;
	int height;
	AvlNode(const int & _element, AvlNode * lt, AvlNode * rt, int h = 0)
		: element(_element), left(lt), right(rt), height(h) {}
};
int height(AvlNode * t)
{
	return NULL == t ? -1 : t->height;
}
void rotateWithLeftChild(AvlNode * & k2)
{
	AvlNode * k1 = k2->left;
	k2->left = k1->right;
	k1->right = k2;
	k2->height = max(height(k2->left), height(k2->right)) + 1;
	k1->height = max(height(k1->left), k2->height) + 1;
	k2 = k1;
	return ;
}
void rotateWithRightChild(AvlNode * & k2)
{
	AvlNode * k1 = k2->right;
	k2->right = k1->left;
	k1->left = k2;
	k2->height = max(height(k2->left), height(k2->right)) + 1;
	k1->height = max(height(k1->right), k2->height) + 1;
	k2 = k1;
	return ;
}
void doubleWithLeftChild(AvlNode * & k)
{
	rotateWithRightChild(k->left);
	rotateWithLeftChild(k);
	return ;
}
void doubleWithRightChild(AvlNode * & k)
{
	rotateWithLeftChild(k->right);
	rotateWithRightChild(k);
	return ;
}
AvlNode * findMin(AvlNode * t)
{
	if (NULL == t)
	{
		return NULL;
	}
	if (NULL == t->left)
	{
		return t;
	}
	return findMin(t->left);
}
AvlNode * findMax(AvlNode * t)
{
	if (NULL == t)
	{
		return NULL;
	}
	if (NULL == t->right)
	{
		return t;
	}
	return findMax(t->right);
}
void insert(const int & x, AvlNode * & t)
{
	if (NULL == t)
	{
		t = new AvlNode(x, NULL, NULL);
	}
	else if (x < t->element)
	{
		insert(x, t->left);
		if (height(t->left) - height(t->right) == 2)
		{
			if (x < t->left->element)
			{
				rotateWithLeftChild(t);
			}
			else
			{
				doubleWithLeftChild(t);
			}
		}
	}
	else if (x > t->element)
	{
		insert(x, t->right);
		if (height(t->right) - height(t->left) == 2)
		{
			if (t->right->element < x)
			{
				rotateWithRightChild(t);
			}
			else
			{
				doubleWithRightChild(t);
			}
		}
	}
	t->height = max(height(t->left), height(t->right)) + 1;
	return ;
}
void remove(const int & x, AvlNode * & t)
{
	if (NULL == t)
	{
		return ;
	}
	if (x < t->element)
	{
		remove(x, t->left);
		if (height(t->right) - height(t->left) == 2)
		{
			AvlNode * rt = t->right;
			if (height(rt->right) > height(rt->left))
			{
				rotateWithRightChild(t);
			}
			else
			{
				doubleWithRightChild(t);
			}
		}
		else
		{
			t->height = max(height(t->left), height(t->right)) + 1;
		}
	}
	else if (t->element < x)
	{
		remove(x, t->right);
		if (height(t->left) - height(t->right) == 2)
		{
			AvlNode * lt = t->left;
			if (height(lt->left) > height(lt->right))
			{
				rotateWithLeftChild(t);
			}
			else
			{
				doubleWithLeftChild(t);
			}
		}
		else
		{
			t->height = max(height(t->left), height(t->right)) + 1;
		}
	}
	else
	{
		if (t->left != NULL && t->right != NULL)
		{
			if (height(t->right) > height(t->left))
			{
				t->element = findMin(t->right)->element;
				remove(t->element, t->right);
			}
			else
			{
				t->element = findMax(t->left)->element;
				remove(t->element, t->left);
			}
		}
		else
		{
			AvlNode * oldNode = t;
			t = (NULL == t->left) ? t->right : t->left;
			delete oldNode;
			oldNode = NULL;
		}
	}
	return ;
}
bool empty(AvlNode * t)
{
	return NULL == t;
}
void clear(AvlNode * & t)
{
	while (!empty(t))
	{
		remove(t->element, t);
	}
	return ;
}
int main()
{
	int n, m;
	AvlNode * root = NULL;
	while (cin >> n >> m)
	{
		for (int i = 0; i < n; ++i)
		{
			int data;
			cin >> data;
			insert(data, root);
		}
		while (m--)
		{
			int op, data;
			cin >> op;
			switch(op)
			{
				case 0:
				cout << findMin(root)->element << endl;
				break ;
				
				case 1:
				cout << findMax(root)->element << endl;
				break ;

				case 2:
				cin >> data;
				insert(data, root);
				break ;
				
				case 3:
				cin >> data;
				remove(data, root);
				break ;
				
				default: break;
			}
		}
	}
	return 0;
}