public class Solution
extends Object
687 - Longest Univalue Path\.
Medium
Given the `root` of a binary tree, return _the length of the longest path, where each node in the path has the same value_. This path may or may not pass through the root.
**The length of the path** between two nodes is represented by the number of edges between them.
**Example 1:**
**Input:** root = [5,4,5,1,1,5]
**Output:** 2
**Example 2:**
**Input:** root = [1,4,5,4,4,5]
**Output:** 2
**Constraints:**
* The number of nodes in the tree is in the range [0, 104].
* `-1000 <= Node.val <= 1000`
* The depth of the tree will not exceed `1000`.