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    "data": {
        "question": {
            "questionId": "173",
            "questionFrontendId": "173",
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            "title": "Binary Search Tree Iterator",
            "titleSlug": "binary-search-tree-iterator",
            "content": "<p>Implement the <code>BSTIterator</code> class that represents an iterator over the <strong><a href=\"https://en.wikipedia.org/wiki/Tree_traversal#In-order_(LNR)\" target=\"_blank\">in-order traversal</a></strong> of a binary search tree (BST):</p>\n\n<ul>\n\t<li><code>BSTIterator(TreeNode root)</code> Initializes an object of the <code>BSTIterator</code> class. The <code>root</code> of the BST is given as part of the constructor. The pointer should be initialized to a non-existent number smaller than any element in the BST.</li>\n\t<li><code>boolean hasNext()</code> Returns <code>true</code> if there exists a number in the traversal to the right of the pointer, otherwise returns <code>false</code>.</li>\n\t<li><code>int next()</code> Moves the pointer to the right, then returns the number at the pointer.</li>\n</ul>\n\n<p>Notice that by initializing the pointer to a non-existent smallest number, the first call to <code>next()</code> will return the smallest element in the BST.</p>\n\n<p>You may assume that <code>next()</code> calls will always be valid. That is, there will be at least a next number in the in-order traversal when <code>next()</code> is called.</p>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2018/12/25/bst-tree.png\" style=\"width: 189px; height: 178px;\" />\n<pre>\n<strong>Input</strong>\n[&quot;BSTIterator&quot;, &quot;next&quot;, &quot;next&quot;, &quot;hasNext&quot;, &quot;next&quot;, &quot;hasNext&quot;, &quot;next&quot;, &quot;hasNext&quot;, &quot;next&quot;, &quot;hasNext&quot;]\n[[[7, 3, 15, null, null, 9, 20]], [], [], [], [], [], [], [], [], []]\n<strong>Output</strong>\n[null, 3, 7, true, 9, true, 15, true, 20, false]\n\n<strong>Explanation</strong>\nBSTIterator bSTIterator = new BSTIterator([7, 3, 15, null, null, 9, 20]);\nbSTIterator.next();    // return 3\nbSTIterator.next();    // return 7\nbSTIterator.hasNext(); // return True\nbSTIterator.next();    // return 9\nbSTIterator.hasNext(); // return True\nbSTIterator.next();    // return 15\nbSTIterator.hasNext(); // return True\nbSTIterator.next();    // return 20\nbSTIterator.hasNext(); // return False\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li>The number of nodes in the tree is in the range <code>[1, 10<sup>5</sup>]</code>.</li>\n\t<li><code>0 &lt;= Node.val &lt;= 10<sup>6</sup></code></li>\n\t<li>At most <code>10<sup>5</sup></code> calls will be made to <code>hasNext</code>, and <code>next</code>.</li>\n</ul>\n\n<p>&nbsp;</p>\n<p><strong>Follow up:</strong></p>\n\n<ul>\n\t<li>Could you implement <code>next()</code> and <code>hasNext()</code> to run in average <code>O(1)</code> time and use&nbsp;<code>O(h)</code> memory, where <code>h</code> is the height of the tree?</li>\n</ul>\n",
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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 BSTIterator {\npublic:\n    BSTIterator(TreeNode* root) {\n        \n    }\n    \n    int next() {\n        \n    }\n    \n    bool hasNext() {\n        \n    }\n};\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * BSTIterator* obj = new BSTIterator(root);\n * int param_1 = obj->next();\n * bool param_2 = obj->hasNext();\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "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 BSTIterator {\n\n    public BSTIterator(TreeNode root) {\n        \n    }\n    \n    public int next() {\n        \n    }\n    \n    public boolean hasNext() {\n        \n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * BSTIterator obj = new BSTIterator(root);\n * int param_1 = obj.next();\n * boolean param_2 = obj.hasNext();\n */",
                    "__typename": "CodeSnippetNode"
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                    "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 BSTIterator(object):\n\n    def __init__(self, root):\n        \"\"\"\n        :type root: TreeNode\n        \"\"\"\n        \n\n    def next(self):\n        \"\"\"\n        :rtype: int\n        \"\"\"\n        \n\n    def hasNext(self):\n        \"\"\"\n        :rtype: bool\n        \"\"\"\n        \n\n\n# Your BSTIterator object will be instantiated and called as such:\n# obj = BSTIterator(root)\n# param_1 = obj.next()\n# param_2 = obj.hasNext()",
                    "__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 BSTIterator:\n\n    def __init__(self, root: Optional[TreeNode]):\n        \n\n    def next(self) -> int:\n        \n\n    def hasNext(self) -> bool:\n        \n\n\n# Your BSTIterator object will be instantiated and called as such:\n# obj = BSTIterator(root)\n# param_1 = obj.next()\n# param_2 = obj.hasNext()",
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                {
                    "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\n\ntypedef struct {\n    \n} BSTIterator;\n\n\nBSTIterator* bSTIteratorCreate(struct TreeNode* root) {\n    \n}\n\nint bSTIteratorNext(BSTIterator* obj) {\n  \n}\n\nbool bSTIteratorHasNext(BSTIterator* obj) {\n  \n}\n\nvoid bSTIteratorFree(BSTIterator* obj) {\n    \n}\n\n/**\n * Your BSTIterator struct will be instantiated and called as such:\n * BSTIterator* obj = bSTIteratorCreate(root);\n * int param_1 = bSTIteratorNext(obj);\n \n * bool param_2 = bSTIteratorHasNext(obj);\n \n * bSTIteratorFree(obj);\n*/",
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                {
                    "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 BSTIterator {\n\n    public BSTIterator(TreeNode root) {\n        \n    }\n    \n    public int Next() {\n        \n    }\n    \n    public bool HasNext() {\n        \n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * BSTIterator obj = new BSTIterator(root);\n * int param_1 = obj.Next();\n * bool param_2 = obj.HasNext();\n */",
                    "__typename": "CodeSnippetNode"
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                    "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 {TreeNode} root\n */\nvar BSTIterator = function(root) {\n    \n};\n\n/**\n * @return {number}\n */\nBSTIterator.prototype.next = function() {\n    \n};\n\n/**\n * @return {boolean}\n */\nBSTIterator.prototype.hasNext = function() {\n    \n};\n\n/** \n * Your BSTIterator object will be instantiated and called as such:\n * var obj = new BSTIterator(root)\n * var param_1 = obj.next()\n * var param_2 = obj.hasNext()\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "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\nclass BSTIterator\n\n=begin\n    :type root: TreeNode\n=end\n    def initialize(root)\n        \n    end\n\n\n=begin\n    :rtype: Integer\n=end\n    def next()\n        \n    end\n\n\n=begin\n    :rtype: Boolean\n=end\n    def has_next()\n        \n    end\n\n\nend\n\n# Your BSTIterator object will be instantiated and called as such:\n# obj = BSTIterator.new(root)\n# param_1 = obj.next()\n# param_2 = obj.has_next()",
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                {
                    "lang": "Swift",
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                    "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 */\n\nclass BSTIterator {\n\n    init(_ root: TreeNode?) {\n        \n    }\n    \n    func next() -> Int {\n        \n    }\n    \n    func hasNext() -> Bool {\n        \n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * let obj = BSTIterator(root)\n * let ret_1: Int = obj.next()\n * let ret_2: Bool = obj.hasNext()\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "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 */\ntype BSTIterator struct {\n    \n}\n\n\nfunc Constructor(root *TreeNode) BSTIterator {\n    \n}\n\n\nfunc (this *BSTIterator) Next() int {\n    \n}\n\n\nfunc (this *BSTIterator) HasNext() bool {\n    \n}\n\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * obj := Constructor(root);\n * param_1 := obj.Next();\n * param_2 := obj.HasNext();\n */",
                    "__typename": "CodeSnippetNode"
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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 */\nclass BSTIterator(_root: TreeNode) {\n\n    def next(): Int = {\n        \n    }\n\n    def hasNext(): Boolean = {\n        \n    }\n\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * var obj = new BSTIterator(root)\n * var param_1 = obj.next()\n * var param_2 = obj.hasNext()\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 BSTIterator(root: TreeNode?) {\n\n    fun next(): Int {\n        \n    }\n\n    fun hasNext(): Boolean {\n        \n    }\n\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * var obj = BSTIterator(root)\n * var param_1 = obj.next()\n * var param_2 = obj.hasNext()\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "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// }\nstruct BSTIterator {\n\n}\n\n\n/** \n * `&self` means the method takes an immutable reference.\n * If you need a mutable reference, change it to `&mut self` instead.\n */\nimpl BSTIterator {\n\n    fn new(root: Option<Rc<RefCell<TreeNode>>>) -> Self {\n        \n    }\n    \n    fn next(&self) -> i32 {\n        \n    }\n    \n    fn has_next(&self) -> bool {\n        \n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * let obj = BSTIterator::new(root);\n * let ret_1: i32 = obj.next();\n * let ret_2: bool = obj.has_next();\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 BSTIterator {\n    /**\n     * @param TreeNode $root\n     */\n    function __construct($root) {\n        \n    }\n  \n    /**\n     * @return Integer\n     */\n    function next() {\n        \n    }\n  \n    /**\n     * @return Boolean\n     */\n    function hasNext() {\n        \n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * $obj = BSTIterator($root);\n * $ret_1 = $obj->next();\n * $ret_2 = $obj->hasNext();\n */",
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                    "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\nclass BSTIterator {\n    constructor(root: TreeNode | null) {\n\n    }\n\n    next(): number {\n\n    }\n\n    hasNext(): boolean {\n\n    }\n}\n\n/**\n * Your BSTIterator object will be instantiated and called as such:\n * var obj = new BSTIterator(root)\n * var param_1 = obj.next()\n * var param_2 = obj.hasNext()\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 bst-iterator%\n  (class object%\n    (super-new)\n\n    ; root : (or/c tree-node? #f)\n    (init-field\n      root)\n    \n    ; next : -> exact-integer?\n    (define/public (next)\n\n      )\n    ; has-next : -> boolean?\n    (define/public (has-next)\n\n      )))\n\n;; Your bst-iterator% object will be instantiated and called as such:\n;; (define obj (new bst-iterator% [root root]))\n;; (define param_1 (send obj next))\n;; (define param_2 (send obj has-next))",
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                    "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 bst_iterator_init_(Root :: #tree_node{} | null) -> any().\nbst_iterator_init_(Root) ->\n  .\n\n-spec bst_iterator_next() -> integer().\nbst_iterator_next() ->\n  .\n\n-spec bst_iterator_has_next() -> boolean().\nbst_iterator_has_next() ->\n  .\n\n\n%% Your functions will be called as such:\n%% bst_iterator_init_(Root),\n%% Param_1 = bst_iterator_next(),\n%% Param_2 = bst_iterator_has_next(),\n\n%% bst_iterator_init_ will be called before every test case, in which you can do some necessary initializations.",
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                    "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 BSTIterator do\n  @spec init_(root :: TreeNode.t | nil) :: any\n  def init_(root) do\n\n  end\n\n  @spec next() :: integer\n  def next() do\n\n  end\n\n  @spec has_next() :: boolean\n  def has_next() do\n\n  end\nend\n\n# Your functions will be called as such:\n# BSTIterator.init_(root)\n# param_1 = BSTIterator.next()\n# param_2 = BSTIterator.has_next()\n\n# BSTIterator.init_ will be called before every test case, in which you can do some necessary initializations.",
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            "sampleTestCase": "[\"BSTIterator\",\"next\",\"next\",\"hasNext\",\"next\",\"hasNext\",\"next\",\"hasNext\",\"next\",\"hasNext\"]\n[[[7,3,15,null,null,9,20]],[],[],[],[],[],[],[],[],[]]",
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Java 8 features such as lambda expressions and stream API can be used. </p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\\r\\n\\r\\n<p>Note that Python 2.7 <a href=\\\"https://www.python.org/dev/peps/pep-0373/\\\" target=\\\"_blank\\\">will not be maintained past 2020</a>. For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu99 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</code>). <a href=\\\"https://github.com/google/sanitizers/wiki/AddressSanitizer\\\" target=\\\"_blank\\\">AddressSanitizer</a> is also enabled to help detect out-of-bounds and use-after-free bugs.</p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n\\r\\n<p>For hash table operations, you may use <a href=\\\"https://troydhanson.github.io/uthash/\\\" target=\\\"_blank\\\">uthash</a>. \\\"uthash.h\\\" is included by default. Below are some examples:</p>\\r\\n\\r\\n<p><b>1. Adding an item to a hash.</b>\\r\\n<pre>\\r\\nstruct hash_entry {\\r\\n    int id;            /* we'll use this field as the key */\\r\\n    char name[10];\\r\\n    UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n    HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>2. Looking up an item in a hash:</b>\\r\\n<pre>\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n    struct hash_entry *s;\\r\\n    HASH_FIND_INT(users, &user_id, s);\\r\\n    return s;\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>3. Deleting an item in a hash:</b>\\r\\n<pre>\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n    HASH_DEL(users, user);  \\r\\n}\\r\\n</pre>\\r\\n</p>\"], \"csharp\": [\"C#\", \"<p><a href=\\\"https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-9\\\" target=\\\"_blank\\\">C# 10 with .NET 6 runtime</a></p>\\r\\n\\r\\n<p>Your code is compiled with debug flag enabled (<code>/debug</code>).</p>\"], \"javascript\": [\"JavaScript\", \"<p><code>Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES6 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\\r\\n\\r\\n<p>For Priority Queue / Queue data structures, you may use <a href=\\\"https://github.com/datastructures-js/priority-queue\\\" target=\\\"_blank\\\">datastructures-js/priority-queue</a> and <a href=\\\"https://github.com/datastructures-js/queue\\\" target=\\\"_blank\\\">datastructures-js/queue</a>.</p>\"], \"ruby\": [\"Ruby\", \"<p><code>Ruby 3.1</code></p>\\r\\n\\r\\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>\"], \"swift\": [\"Swift\", \"<p><code>Swift 5.5.2</code>.</p>\"], \"golang\": [\"Go\", \"<p><code>Go 1.17.6</code>.</p>\\r\\n\\r\\n<p>Support <a href=\\\"https://godoc.org/github.com/emirpasic/gods\\\" target=\\\"_blank\\\">https://godoc.org/github.com/emirpasic/gods</a> library.</p>\"], \"python3\": [\"Python3\", \"<p><code>Python 3.10</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/3/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/3/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/3/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\"], \"scala\": [\"Scala\", \"<p><code>Scala 2.13.7</code>.</p>\"], \"kotlin\": [\"Kotlin\", \"<p><code>Kotlin 1.3.10</code>.</p>\"], \"rust\": [\"Rust\", \"<p><code>Rust 1.58.1</code></p>\\r\\n\\r\\n<p>Supports <a href=\\\"https://crates.io/crates/rand\\\" target=\\\"_blank\\\">rand </a> v0.6\\u00a0from crates.io</p>\"], \"php\": [\"PHP\", \"<p><code>PHP 8.1</code>.</p>\\r\\n<p>With bcmath module</p>\"], \"typescript\": [\"Typescript\", \"<p><code>TypeScript 4.5.4, Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES2020 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\"], \"racket\": [\"Racket\", \"<p>Run with <code>Racket 8.3</code>.</p>\"], \"erlang\": [\"Erlang\", \"Erlang/OTP 24.2\"], \"elixir\": [\"Elixir\", \"Elixir 1.13.0 with Erlang/OTP 24.2\"]}",
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