数据结构：根据有序链表构造平衡二叉树

#include <iostream>
#include <stack>
using namespace std;

struct Node
{
	int data;
	Node* next;
	Node(int d = int()):data(d){}
};
class List
{
	friend class T;
	public:
	List():first(NULL){}
	void Insert(int a[],int n)
	{
		Node *p = NULL;
		for(int i=0;i<n;i++)
		{
				Node *s = new Node(a[i]);
				if(first==NULL)
				{
					first=s;
					p=s;
				}
				else
				{
					s->next = p->next;
					p->next = s;
					p = s;
				}
		}
	}
	void Printf()
	{
		Node* p = first;
		while(p!=NULL)
		{
			cout<<p->data<<" ";
			p=p->next;
		}
		cout<<endl;
	}
	private:
	Node *first;
};
/////////////////////////////////
struct tNode
{
	int val;
	int bf;//平衡因子。
	tNode *left;
	tNode *right;
	tNode(int d = int()):val(d),left(NULL),right(NULL),bf(0){}
};

class T
{
	public:
	T():root(NULL){}
	void Create(List &list)
	{
		Node *p = list.first;
		tNode *q = NULL;
		while(p!=NULL)
		{
			tNode *s = new tNode(p->data);
			if(root==NULL)
			{
				root = s;
				q = s;
			}
			else
			{
			   tNode* pr = 	NULL;
 				 stack<tNode*> st;
				 while(q->right!=NULL)
					{
						pr=q;
						st.push(pr);
						q=q->right;
					}
					s->right = q->right;
					q->right = s;

					int count = 0;
					while(st.empty()==false)
					{
					  tNode *tnode = st.top();
						st.pop();
						if(tnode->val>q->val)
							tnode->bf--;
						else
							tnode->bf++;
						if(tnode->bf==0)
							{
							break;
							}
						else if(tnode->bf==1)
							{
							continue;
							}
						else
							{
							 tNode* temp = NULL;
							int flags = 0;
							 if(st.empty()==true)
									root=q;//判断是否是根节点旋转。
							 else
								{
							    temp = st.top();
									st.pop();
									if(temp->right==tnode)
										flags=1;
									else
										flags=-1;
								}
							  LR(tnode,q);//旋转。
								if(flags==1)
								{
									temp->right=q;
								}
								else
								{
									temp->left=q;
								}
							 break;
							}
						q=tnode;
					}
				}
			p=p->next;
		}
	}
	void LR(tNode* &t,tNode* &p)
	{
			t->right = p->left;
			p->left = t;
			p->bf=0;
			t->bf=0;
	}
	void Printf()
	{
		Printf(root);
	}
	private:
	void Printf(tNode *t)
	{
		if(t==NULL)return;
		else
		{
			Printf(t->left);
			cout<<t->val<<" ";
			Printf(t->right);
		}
	}
	private:
	tNode *root;
};

int main()
{
	int a[] = {1,2,3,4,5,6,7,8,9};
	List list;
	list.Insert(a,sizeof(a)/sizeof(int));
	T t;
	t.Create(list);
	t.Printf();//二叉树中序打印。
	return 0;
}

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