Find Original-Node Common Ancestors in a Search Tree
Company: Google
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: medium
Interview Round: Other
### Problem
Given a BST root and two different original nodes p and q in it, return their lowest common ancestor node. A node counts as its own ancestor. Preserve all three TreeNode* arguments and the TreeNode* result.
```cpp
TreeNode* lowestCommonAncestor(TreeNode* root, TreeNode* p, TreeNode* q);
```
### Examples
```text
root = [7,3,11,1,5,9,13], p = node 3, q = node 5 -> original node 3
root = [7,3,11,1,5,9,13], p = node 1, q = node 13 -> original node 7
```
### Constraints
- There are 2 through 100000 nodes with unique values in [-1000000000,1000000000].
- p and q differ and both belong to the tree.
Overview: Find Original-Node Common Ancestors in a Search Tree. Given a BST root and two different original nodes p and q in it, return their lowest common ancestor node. A node counts as its own ancestor. Preserve all three