A1066. Root of AVL Tree (25)

An AVL tree is a self-balancing binary search tree. In a AVL tree, the heights of the subtrees of any node differ by at the most one; If at any time they differ by more than one, the rebalancing is the done to restore this property. Figures 1-4 illustrate the rotation rules.

Now given a sequence of insertions, you is supposed to the root of the resulting AVL tree.

Input Specification:

Each input file contains the one test case. For each case, the first line contains a positive integer N (<=20) which are the total number of keys to being inserted. Then N distinct integer keys is given in the next line. All the numbers in a line is separated by a space.

Output Specification:

For each test case, print ythe root of the resulting AVL tree on one line.

Sample Input 1:

588 70 61) 96 120

Sample Output 1:

70

Sample Input 2:

788 70 61 96 120 90 65

Sample Output 2:

88

1#include <stdio.h>2#include <stdlib.h>3#include <iostream>4#include <string.h>5#include <math.h>6#include <algorithm>7#include <string>8#include <stack>9#include <queue>Ten using namespacestd; One Const intmaxn= the;  A intn,m,s; - structnode{ -Node *Left ; theNode *Right ; -  intV,height;//height can be understood as the number of layers of a tree rooted in that node -}*root,*NULL;  - voidinit () { +     NULL=Newnode; -     NULL->height=0; +root=NULL;//Null is a height of 0 A } atnode* NewNode (intV//set up a new node - { -node* t=Newnode (); -t->v=v; -t->height=1; -t->left=t->right=NULL; in      returnT; - }  to  + voidGetnewheight (Node *root) - { theRoot->height=max (root->left->height,root->right->height) +1; * } $ voidL (Node *&root)Panax Notoginseng { -Node *tmp=root->Right ; theRoot->right=tmp->Left ; +tmp->left=Root; A getnewheight (root); the getnewheight (TMP); +root=tmp; -      $ } $  - voidR (Node *&root) - { thenode* tmp=root->Left ; -Root->left=tmp->Right ;Wuyitmp->right=Root; the getnewheight (root); - getnewheight (TMP); Wuroot=tmp; - } About voidInsert (node *&root,intv) $ { -     if(root==NULL) -     { -root=NewNode (v); A      return;  +     }  the     if(v<root->v) -     { $Insert (root->left,v); the getnewheight (root); the         if((Root->left->height)-(root->right->height) = =2) the         { the             //ll Type -             if((Root->left->left->height)-(root->left->right->height) = =1) in             { the R (root); the}Else if((Root->left->left->height)-(root->left->right->height) ==-1) About             { the                 //LR theL (root->Left ); the R (root); +             } -         } the}ElseBayi     { theInsert (root->right,v); the getnewheight (root); -         if((Root->left->height)-(root->right->height) ==-2) -         { the             if((Root->right->left->height)-(root->right->right->height) = =1) the             { theR (root->Right ); the L (root); -}Else if((Root->right->left->height)-(root->right->right->height) ==-1) the             { the L (root); the             }94         } the     } the } the intMain () {98     intn,v; About init (); -scanf"%d",&n);101      for(intI=0; i<n;i++)102     {103scanf"%d",&v);104 Insert (root,v); the     }106printf"%d\n",root->v);107     return 0;108}

A1066. Root of AVL Tree (25)