# Problem 20: Sorting Discordance (BST)

## Problem Statement
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.

## Input Format
- The `root` of a distorted BST.

## Example
**Input:** root = [1, 3, null, null, 2]  
**Output:** [3, 1, null, null, 2]
**Explanation:** Nodes 1 and 3 were swapped.