public class Solution
extends Object
662 - Maximum Width of Binary Tree\.
Medium
Given the `root` of a binary tree, return _the **maximum width** of the given tree_.
The **maximum width** of a tree is the maximum **width** among all levels.
The **width** of one level is defined as the length between the end-nodes (the leftmost and rightmost non-null nodes), where the null nodes between the end-nodes are also counted into the length calculation.
It is **guaranteed** that the answer will in the range of **32-bit** signed integer.
**Example 1:**
**Input:** root = [1,3,2,5,3,null,9]
**Output:** 4
**Explanation:** The maximum width existing in the third level with the length 4 (5,3,null,9).
**Example 2:**
**Input:** root = [1,3,null,5,3]
**Output:** 2
**Explanation:** The maximum width existing in the third level with the length 2 (5,3).
**Example 3:**
**Input:** root = [1,3,2,5]
**Output:** 2
**Explanation:** The maximum width existing in the second level with the length 2 (3,2).
**Constraints:**
* The number of nodes in the tree is in the range `[1, 3000]`.
* `-100 <= Node.val <= 100`