Package g0901_1000.s0919_complete_binary_tree_inserter

Class 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 Detail

      • CBTInserter

        public CBTInserter​(TreeNode root)

    • Method Detail

      • insert

        public int insert​(int val)