Two elements of a binary search tree (BST) are swapped by mistake.

Recover the tree without changing its structure.

Note:
A solution using O(n) space is pretty straight forward. Could you devise a constant space solution?

/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode(int x) : val(x), left(NULL), right(NULL) {}
* };
*/
class Solution {
public:
void recoverTree(TreeNode* root) {
stack<TreeNode*> s;
TreeNode *p = root, *last = NULL, *p1 = NULL, *p2 = NULL;
while(p || !s.empty())
{
while(p)
{
s.push(p);
p = p->left;
}
if(!s.empty())
{
p = s.top();
s.pop();
if(last && last->val >= p->val)
{
p2 = p;
if(!p1)
p1 = last;
else
break;
}
last = p;
p = p->right;
}
}
swap(p1->val, p2->val);
}
};

99. Recover Binary Search Tree -- 找到二叉排序树中交换过位置的两个节点的更多相关文章

  1. 【LeetCode】99. Recover Binary Search Tree 解题报告(Python)

    [LeetCode]99. Recover Binary Search Tree 解题报告(Python) 标签(空格分隔): LeetCode 题目地址:https://leetcode.com/p ...

  2. Leetcode 笔记 99 - Recover Binary Search Tree

    题目链接:Recover Binary Search Tree | LeetCode OJ Two elements of a binary search tree (BST) are swapped ...

  3. [LeetCode] 99. Recover Binary Search Tree(复原BST) ☆☆☆☆☆

    Recover Binary Search Tree leetcode java https://leetcode.com/problems/recover-binary-search-tree/di ...

  4. 【LeetCode】99. Recover Binary Search Tree

    Recover Binary Search Tree Two elements of a binary search tree (BST) are swapped by mistake. Recove ...

  5. [LeetCode] 99. Recover Binary Search Tree 复原二叉搜索树

    Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing ...

  6. 【LeetCode】 99. Recover Binary Search Tree [Hard] [Morris Traversal] [Tree]

    Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing ...

  7. leetcode 99 Recover Binary Search Tree ----- java

    Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing ...

  8. 99. Recover Binary Search Tree

    题目: Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without chan ...

  9. LeetCode OJ 99. Recover Binary Search Tree

    Two elements of a binary search tree (BST) are swapped by mistake. Recover the tree without changing ...

随机推荐

  1. 【elasticsearch 依赖 urllib3 请问 是否 urllib3和阿里es、oss的对接出现异常】

    During handling of the above exception, another exception occurred: Traceback (most recent call last ...

  2. Python爬虫基础(一)urllib2库的基本使用

    爬虫也就是所谓的网络数据采集,是一种通过多种手段收集网络数据的方式,不光是通过与 API 交互(或者直接与浏览器交互)的方式.最常用的方法是写一个自动化程序向网络服务器请求数据(通常是用 HTML 表 ...

  3. Git 基本操作(二)

    1. 分支操作 1.1 Fast-forward 当被合并分支(C4)位于合并分支(C2)的历史线上,此时的合并称为"fast-forward"; // hotfix 被合并到 m ...

  4. Notepad++插件安装和使用和打开大文件

    版权声明:本文为博主皮皮http://blog.csdn.net/pipisorry原创文章,未经博主同意不得转载. https://blog.csdn.net/pipisorry/article/d ...

  5. git-【一】概述安装

    一:Git是什么? Git是目前世界上最先进的分布式版本控制系统. 二:SVN与Git的最主要的区别? SVN是集中式版本控制系统,版本库是集中放在中央服务器的,而干活的时候,用的都是自己的电脑,所以 ...

  6. sql 用xml方式插入数据乱码问题解决方法

    sql 使用存储过程 参数为xml字符串 xml不要写编码,如下 <?xml version=\"1.0\" ?><root>数据字符串</root& ...

  7. jsp内置对象与servlet的关系

      Servlet与JSP九大内置对象的关系 JSP对象 怎样获得 out->response.getWriter request ->Service方法中的req参数 response  ...

  8. 3.12 Templates -- Wrting Helpers(编写辅助器)

    一.概述 1. Helpers允许你向你的模板添加超出在Ember中开箱即用的额外的功能.辅助器是最有用的,用于将来自模型和组件的原始值转换成更适合于用户的格式. 2. 例如,假设我们有一个Invoi ...

  9. web服务器配置实践

    1.为linux系统分配IP地址:192.168.X.1/24,客户端XP系统IP地址为:192.168.X.2/24,其主要DNS指定为:192.168.X.1. 2.查询本机是否安装了httpd服 ...

  10. Polya

    using namespace std; typedef long long LL; const int MAXN = 1e3 +10; const LL MOD = (LL)1 << 6 ...