g0901_1000.s0919_complete_binary_tree_inserter

Class CBTInserter

java.lang.Object

g0901_1000.s0919_complete_binary_tree_inserter.CBTInserter

public class CBTInserter
extends Object

919 - Complete Binary Tree Inserter.

Medium

A complete binary tree is a binary tree in which every level, except possibly the last, is completely filled, and all nodes are as far left as possible.

Design an algorithm to insert a new node to a complete binary tree keeping it complete after the insertion.

Implement the CBTInserter class:

• CBTInserter(TreeNode root) Initializes the data structure with the root of the complete binary tree.
• int insert(int v) Inserts a TreeNode into the tree with value Node.val == val so that the tree remains complete, and returns the value of the parent of the inserted TreeNode.
• TreeNode get_root() Returns the root node of the tree.

Example 1:

Input [“CBTInserter”, “insert”, “insert”, “get_root”] [[[1, 2]], [3], [4], []]

Output: [null, 1, 2, [1, 2, 3, 4]]

Explanation:

CBTInserter cBTInserter = new CBTInserter([1, 2]); 
cBTInserter.insert(3); // return 1 
cBTInserter.insert(4); // return 2 
cBTInserter.get\_root(); // return [1, 2, 3, 4]

Constraints:

• The number of nodes in the tree will be in the range [1, 1000].
• 0 <= Node.val <= 5000
• root is a complete binary tree.
• 0 <= val <= 5000
• At most 104 calls will be made to insert and get_root.

Constructor Summary

Constructors

Constructor and Description
CBTInserter(TreeNode root)

Method Summary

Modifier and Type	Method and Description
TreeNode	getRoot()
int	insert(int val)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

CBTInserter

public CBTInserter(TreeNode root)

Method Detail

insert

public int insert(int val)

getRoot

public TreeNode getRoot()