Solution (leetcode-in-java 1.21 API)

java.lang.Object
- g0001_0100.s0099_recover_binary_search_tree.Solution

```
public class Solution
extends Object
```
99 - Recover Binary Search Tree.
Medium

You are given the root of a binary search tree (BST), where the values of exactly two nodes of the tree were swapped by mistake. Recover the tree without changing its structure.

Example 1:

Input: root = [1,3,null,null,2]

Output: [3,1,null,null,2]

Explanation: 3 cannot be a left child of 1 because 3 > 1. Swapping 1 and 3 makes the BST valid.

Example 2:

Input: root = [3,1,4,null,null,2]

Output: [2,1,4,null,null,3]

Explanation: 2 cannot be in the right subtree of 3 because 2 < 3. Swapping 2 and 3 makes the BST valid.

Constraints:
- The number of nodes in the tree is in the range [2, 1000].
- -2³¹ <= Node.val <= 2³¹ - 1
Follow up: A solution using O(n) space is pretty straight-forward. Could you devise a constant O(1) space solution?

- Constructor Summary
  
  Constructors
  Constructor Description
  
  Solution()
- Method Summary
  
  All Methods Instance Methods Concrete Methods
  Modifier and Type Method Description
  
  void recoverTree(TreeNode root)
  - Methods inherited from class java.lang.Object
    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail
- Solution
```
public Solution()
```

Method Detail

recoverTree

public void recoverTree(TreeNode root)