#include <stdio.h>
#include <stdlib.h>

typedef struct BiTNode
{
    int data;
    int bf;//节点平衡因子
    struct BiTNode *lchild, *rchild;
}BiTNode, *BiTree;//二叉树结构

void Right(BiTree &p)
{
    BiTree L;
    L = p->lchild;
    p->lchild = L->rchild;
    L->rchild = p;
    p = L;
}

void Left(BiTree &p)
{
    BiTree R;
    R = p->rchild;
    p->rchild = R->lchild;
    R->lchild = p;
    p = R;
}

void LeftBalance(BiTree &T)
{
    BiTree L,Lr;
    L = T->lchild;
    switch (L->bf)
    {
    case 1:
        T->bf = L->bf = 0;
        Right(T);
        break;
    case -1:
        Lr = L->rchild;
        switch (Lr->bf)
        {
        case 1:
            T->bf = -1;
            L->bf = 0;
            break;
        case 0:
            T->bf = L->bf = 0;
            break;
        case -1:
            T->bf = 0;
            L->bf = 1;
            break;
        }
        Lr->bf = 0;
        Left(T->lchild);
        Right(T);
    }
}

void RightBalance(BiTree &T)
{
    BiTree R, Rl;
    R = T->rchild;
    switch (R->bf)
    {
    case -1:
        T->bf = R->bf = 0;
        Left(T);
        break;
    case 1:
        Rl = R->lchild;
        switch (Rl->bf)
        {
        case -1:
            T->bf = 1;
            R->bf = 0;
            break;
        case 0:
            T->bf = R->bf = 0;
            break;
        case 1:
            T->bf = 0;
            R->bf = -1;
            break;
        }
        Rl->bf = 0;
        Right(T->rchild);
        Left(T);
    }
}

int InserAVL(BiTree &T, int k, int &taller)
{
    if (!T)
    {
        T = (BiTree)malloc(sizeof(BiTNode));
        T->data = k;
        T->rchild = T->lchild = NULL;
        T->bf = 0;
        taller = true;
    }

    else
    {
        if (k == T->data)
        {
            taller = false;
            printf("元素已存在");
            return false;
        }
        if (k < T->data)
        {
            if (taller)
            {
                switch (T->bf)
                {
                case 1:
                    LeftBalance(T);
                    taller = false;
                    break;
                case 0:
                    T->bf = 1;
                    taller = true;
                    break;
                case -1:
                    T->bf = 0;
                    taller = false;
                    break;
                }
            }
        }
        else
        {
            if (taller)
            {
                switch (T->bf)
                {
                case 1:
                    T->bf = 0;
                    taller = false;
                    break;
                case 0:
                    T->bf = -1;
                    taller = true;
                    break;
                case -1:
                    RightBalance(T);
                    taller = false;
                    break;
                }
            }
        }
    }
    return true;
}

void InOrder(BiTree T)
{
    InOrder(T->lchild);
    printf("%d ", T->data);
    InOrder(T->rchild);
}
int main()
{
    int  i;
    int a[10] = {3,2,1,4,5,6,7,10,9,8};
    BiTree T = NULL;
    int taller;
    printf("输入序列");
    for (i = 0; i < 10; i++)
    {
        //scanf_s("%d", &a);
        InserAVL(T, a[i], taller);
    }
    InOrder(T);
}