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    "data": {
        "question": {
            "questionId": "2306",
            "questionFrontendId": "2196",
            "boundTopicId": null,
            "title": "Create Binary Tree From Descriptions",
            "titleSlug": "create-binary-tree-from-descriptions",
            "content": "<p>You are given a 2D integer array <code>descriptions</code> where <code>descriptions[i] = [parent<sub>i</sub>, child<sub>i</sub>, isLeft<sub>i</sub>]</code> indicates that <code>parent<sub>i</sub></code> is the <strong>parent</strong> of <code>child<sub>i</sub></code> in a <strong>binary</strong> tree of <strong>unique</strong> values. Furthermore,</p>\n\n<ul>\n\t<li>If <code>isLeft<sub>i</sub> == 1</code>, then <code>child<sub>i</sub></code> is the left child of <code>parent<sub>i</sub></code>.</li>\n\t<li>If <code>isLeft<sub>i</sub> == 0</code>, then <code>child<sub>i</sub></code> is the right child of <code>parent<sub>i</sub></code>.</li>\n</ul>\n\n<p>Construct the binary tree described by <code>descriptions</code> and return <em>its <strong>root</strong></em>.</p>\n\n<p>The test cases will be generated such that the binary tree is <strong>valid</strong>.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2022/02/09/example1drawio.png\" style=\"width: 300px; height: 236px;\" />\n<pre>\n<strong>Input:</strong> descriptions = [[20,15,1],[20,17,0],[50,20,1],[50,80,0],[80,19,1]]\n<strong>Output:</strong> [50,20,80,15,17,19]\n<strong>Explanation:</strong> The root node is the node with value 50 since it has no parent.\nThe resulting binary tree is shown in the diagram.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2022/02/09/example2drawio.png\" style=\"width: 131px; height: 300px;\" />\n<pre>\n<strong>Input:</strong> descriptions = [[1,2,1],[2,3,0],[3,4,1]]\n<strong>Output:</strong> [1,2,null,null,3,4]\n<strong>Explanation:</strong> The root node is the node with value 1 since it has no parent.\nThe resulting binary tree is shown in the diagram.\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= descriptions.length &lt;= 10<sup>4</sup></code></li>\n\t<li><code>descriptions[i].length == 3</code></li>\n\t<li><code>1 &lt;= parent<sub>i</sub>, child<sub>i</sub> &lt;= 10<sup>5</sup></code></li>\n\t<li><code>0 &lt;= isLeft<sub>i</sub> &lt;= 1</code></li>\n\t<li>The binary tree described by <code>descriptions</code> is valid.</li>\n</ul>\n",
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            "difficulty": "Medium",
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            "exampleTestcases": "[[20,15,1],[20,17,0],[50,20,1],[50,80,0],[80,19,1]]\n[[1,2,1],[2,3,0],[3,4,1]]",
            "categoryTitle": "Algorithms",
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            "topicTags": [
                {
                    "name": "Array",
                    "slug": "array",
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                    "__typename": "TopicTagNode"
                },
                {
                    "name": "Hash Table",
                    "slug": "hash-table",
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                    "__typename": "TopicTagNode"
                },
                {
                    "name": "Tree",
                    "slug": "tree",
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                    "name": "Depth-First Search",
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                    "name": "Breadth-First Search",
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                    "name": "Binary Tree",
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                {
                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     TreeNode *left;\n *     TreeNode *right;\n *     TreeNode() : val(0), left(nullptr), right(nullptr) {}\n *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}\n *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}\n * };\n */\nclass Solution {\npublic:\n    TreeNode* createBinaryTree(vector<vector<int>>& descriptions) {\n        \n    }\n};",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Java",
                    "langSlug": "java",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     int val;\n *     TreeNode left;\n *     TreeNode right;\n *     TreeNode() {}\n *     TreeNode(int val) { this.val = val; }\n *     TreeNode(int val, TreeNode left, TreeNode right) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\nclass Solution {\n    public TreeNode createBinaryTree(int[][] descriptions) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Python",
                    "langSlug": "python",
                    "code": "# Definition for a binary tree node.\n# class TreeNode(object):\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution(object):\n    def createBinaryTree(self, descriptions):\n        \"\"\"\n        :type descriptions: List[List[int]]\n        :rtype: Optional[TreeNode]\n        \"\"\"\n        ",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Python3",
                    "langSlug": "python3",
                    "code": "# Definition for a binary tree node.\n# class TreeNode:\n#     def __init__(self, val=0, left=None, right=None):\n#         self.val = val\n#         self.left = left\n#         self.right = right\nclass Solution:\n    def createBinaryTree(self, descriptions: List[List[int]]) -> Optional[TreeNode]:\n        ",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "C",
                    "langSlug": "c",
                    "code": "/**\n * Definition for a binary tree node.\n * struct TreeNode {\n *     int val;\n *     struct TreeNode *left;\n *     struct TreeNode *right;\n * };\n */\n\n\nstruct TreeNode* createBinaryTree(int** descriptions, int descriptionsSize, int* descriptionsColSize){\n\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public int val;\n *     public TreeNode left;\n *     public TreeNode right;\n *     public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {\n *         this.val = val;\n *         this.left = left;\n *         this.right = right;\n *     }\n * }\n */\npublic class Solution {\n    public TreeNode CreateBinaryTree(int[][] descriptions) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "/**\n * Definition for a binary tree node.\n * function TreeNode(val, left, right) {\n *     this.val = (val===undefined ? 0 : val)\n *     this.left = (left===undefined ? null : left)\n *     this.right = (right===undefined ? null : right)\n * }\n */\n/**\n * @param {number[][]} descriptions\n * @return {TreeNode}\n */\nvar createBinaryTree = function(descriptions) {\n    \n};",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "# Definition for a binary tree node.\n# class TreeNode\n#     attr_accessor :val, :left, :right\n#     def initialize(val = 0, left = nil, right = nil)\n#         @val = val\n#         @left = left\n#         @right = right\n#     end\n# end\n# @param {Integer[][]} descriptions\n# @return {TreeNode}\ndef create_binary_tree(descriptions)\n    \nend",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Swift",
                    "langSlug": "swift",
                    "code": "/**\n * Definition for a binary tree node.\n * public class TreeNode {\n *     public var val: Int\n *     public var left: TreeNode?\n *     public var right: TreeNode?\n *     public init() { self.val = 0; self.left = nil; self.right = nil; }\n *     public init(_ val: Int) { self.val = val; self.left = nil; self.right = nil; }\n *     public init(_ val: Int, _ left: TreeNode?, _ right: TreeNode?) {\n *         self.val = val\n *         self.left = left\n *         self.right = right\n *     }\n * }\n */\nclass Solution {\n    func createBinaryTree(_ descriptions: [[Int]]) -> TreeNode? {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Go",
                    "langSlug": "golang",
                    "code": "/**\n * Definition for a binary tree node.\n * type TreeNode struct {\n *     Val int\n *     Left *TreeNode\n *     Right *TreeNode\n * }\n */\nfunc createBinaryTree(descriptions [][]int) *TreeNode {\n    \n}",
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                {
                    "lang": "Scala",
                    "langSlug": "scala",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode(_value: Int = 0, _left: TreeNode = null, _right: TreeNode = null) {\n *   var value: Int = _value\n *   var left: TreeNode = _left\n *   var right: TreeNode = _right\n * }\n */\nobject Solution {\n    def createBinaryTree(descriptions: Array[Array[Int]]): TreeNode = {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Kotlin",
                    "langSlug": "kotlin",
                    "code": "/**\n * Example:\n * var ti = TreeNode(5)\n * var v = ti.`val`\n * Definition for a binary tree node.\n * class TreeNode(var `val`: Int) {\n *     var left: TreeNode? = null\n *     var right: TreeNode? = null\n * }\n */\nclass Solution {\n    fun createBinaryTree(descriptions: Array<IntArray>): TreeNode? {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Rust",
                    "langSlug": "rust",
                    "code": "// Definition for a binary tree node.\n// #[derive(Debug, PartialEq, Eq)]\n// pub struct TreeNode {\n//   pub val: i32,\n//   pub left: Option<Rc<RefCell<TreeNode>>>,\n//   pub right: Option<Rc<RefCell<TreeNode>>>,\n// }\n// \n// impl TreeNode {\n//   #[inline]\n//   pub fn new(val: i32) -> Self {\n//     TreeNode {\n//       val,\n//       left: None,\n//       right: None\n//     }\n//   }\n// }\nuse std::rc::Rc;\nuse std::cell::RefCell;\nimpl Solution {\n    pub fn create_binary_tree(descriptions: Vec<Vec<i32>>) -> Option<Rc<RefCell<TreeNode>>> {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "PHP",
                    "langSlug": "php",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     public $val = null;\n *     public $left = null;\n *     public $right = null;\n *     function __construct($val = 0, $left = null, $right = null) {\n *         $this->val = $val;\n *         $this->left = $left;\n *         $this->right = $right;\n *     }\n * }\n */\nclass Solution {\n\n    /**\n     * @param Integer[][] $descriptions\n     * @return TreeNode\n     */\n    function createBinaryTree($descriptions) {\n        \n    }\n}",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "TypeScript",
                    "langSlug": "typescript",
                    "code": "/**\n * Definition for a binary tree node.\n * class TreeNode {\n *     val: number\n *     left: TreeNode | null\n *     right: TreeNode | null\n *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {\n *         this.val = (val===undefined ? 0 : val)\n *         this.left = (left===undefined ? null : left)\n *         this.right = (right===undefined ? null : right)\n *     }\n * }\n */\n\nfunction createBinaryTree(descriptions: number[][]): TreeNode | null {\n\n};",
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                {
                    "lang": "Racket",
                    "langSlug": "racket",
                    "code": "; Definition for a binary tree node.\n#|\n\n; val : integer?\n; left : (or/c tree-node? #f)\n; right : (or/c tree-node? #f)\n(struct tree-node\n  (val left right) #:mutable #:transparent)\n\n; constructor\n(define (make-tree-node [val 0])\n  (tree-node val #f #f))\n\n|#\n\n(define/contract (create-binary-tree descriptions)\n  (-> (listof (listof exact-integer?)) (or/c tree-node? #f))\n\n  )",
                    "__typename": "CodeSnippetNode"
                },
                {
                    "lang": "Erlang",
                    "langSlug": "erlang",
                    "code": "%% Definition for a binary tree node.\n%%\n%% -record(tree_node, {val = 0 :: integer(),\n%%                     left = null  :: 'null' | #tree_node{},\n%%                     right = null :: 'null' | #tree_node{}}).\n\n-spec create_binary_tree(Descriptions :: [[integer()]]) -> #tree_node{} | null.\ncreate_binary_tree(Descriptions) ->\n  .",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Elixir",
                    "langSlug": "elixir",
                    "code": "# Definition for a binary tree node.\n#\n# defmodule TreeNode do\n#   @type t :: %__MODULE__{\n#           val: integer,\n#           left: TreeNode.t() | nil,\n#           right: TreeNode.t() | nil\n#         }\n#   defstruct val: 0, left: nil, right: nil\n# end\n\ndefmodule Solution do\n  @spec create_binary_tree(descriptions :: [[integer]]) :: TreeNode.t | nil\n  def create_binary_tree(descriptions) do\n\n  end\nend",
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            "hints": [
                "Could you represent and store the descriptions more efficiently?",
                "Could you find the root node?",
                "The node that is not a child in any of the descriptions is the root node."
            ],
            "solution": null,
            "status": null,
            "sampleTestCase": "[[20,15,1],[20,17,0],[50,20,1],[50,80,0],[80,19,1]]",
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