1066 Root of AVL Tree (25)（25 分）

二叉树旋转操作，这个只能记一下怎么旋转了

#include<iostream>
#include<algorithm>
using namespace std;
int n;
struct node {
    int data;
    node *lchild, *rchild;
};
node* Newnode(int x)
{
    node* newnode = new node;
    newnode->data = x;
    newnode->lchild = newnode->rchild = NULL;
    return newnode;
}
int Height(node* root)
{
    if (root == NULL)return 0;
    else return max(Height(root->lchild), Height(root->rchild)) + 1;
}
int getbalance(node* root)
{
    return Height(root->lchild) - Height(root->rchild);
}
void R(node*&root)
{
    node* temp = root->lchild;
    root->lchild = temp->rchild;
    temp->rchild = root;
    root = temp;
}
void L(node*&root)
{
    node* temp = root->rchild;
    root->rchild = temp->lchild;
    temp->lchild = root;
    root = temp;
}
void insert(node* &root, int x)
{
    if (root == NULL)
    {
        root = Newnode(x);
        return;
    }
    if (x < root->data)
    {
        insert(root->lchild, x);
        if (getbalance(root) == 2)
        {
            if (getbalance(root->lchild) == 1)
            {
                R(root);
            }
            else if (getbalance(root->lchild) == -1)
            {
                L(root->lchild);
                R(root);
            }
        }
    }
    else
    {
        insert(root->rchild, x);
        if (getbalance(root) == -2)
        {
            if (getbalance(root->rchild) == -1)L(root);
            else if (getbalance(root->rchild) == 1)
            {
                R(root->rchild);
                L(root);
            }
        }

    }
}
int main()
{
    scanf("%d", &n);
    node *root = NULL;
    for (int i = 0; i < n; i++)
    {
        int x;
        scanf("%d", &x);
        insert(root, x);
    }
    printf("%d", root->data);
    return 0;
}