#998

Maximum Binary Tree II

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Description

A maximum tree is a tree in which every node's value exceeds all values in its subtree.

You are given the root of a maximum binary tree constructed from a list a using the following Construct(a) routine:

- If a is empty, return null.

- Let a[i] be the largest element of a. Create a root node with value a[i].

- The left child is Construct([a[0], ..., a[i-1]]).

- The right child is Construct([a[i+1], ..., a[a.length-1]]).

- Return root.

You are also given an integer val. Let b be a with val appended; all values in b are unique.

Return Construct(b).

Example 1:

Input: root = [4,1,3,null,null,2], val = 5
Output: [5,4,null,1,3,null,null,2]
Explanation: a = [1,4,2,3], b = [1,4,2,3,5]

Example 2:

Input: root = [5,2,4,null,1], val = 3
Output: [5,2,4,null,1,null,3]
Explanation: a = [2,1,5,4], b = [2,1,5,4,3]

Example 3:

Input: root = [5,2,3,null,1], val = 4
Output: [5,2,4,null,1,3]
Explanation: a = [2,1,5,3], b = [2,1,5,3,4]

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