Design Skiplist
<p>Design a <strong>Skiplist</strong> without using any built-in libraries.</p>

<p>A <strong>skiplist</strong> is a data structure that takes <code>O(log(n))</code> time to add, erase and search. Comparing with treap and red-black tree which has the same function and performance, the code length of Skiplist can be comparatively short and the idea behind Skiplists is just simple linked lists.</p>

<p>For example, we have a Skiplist containing <code>[30,40,50,60,70,90]</code> and we want to add <code>80</code> and <code>45</code> into it. The Skiplist works this way:</p>

<p><img alt="" src="https://assets.leetcode.com/uploads/2019/09/27/1506_skiplist.gif" style="width: 500px; height: 173px;" /><br />
<small>Artyom Kalinin [CC BY-SA 3.0], via <a href="https://commons.wikimedia.org/wiki/File:Skip_list_add_element-en.gif" target="_blank" title="Artyom Kalinin [CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0)], via Wikimedia Commons">Wikimedia Commons</a></small></p>

<p>You can see there are many layers in the Skiplist. Each layer is a sorted linked list. With the help of the top layers, add, erase and search can be faster than <code>O(n)</code>. It can be proven that the average time complexity for each operation is <code>O(log(n))</code> and space complexity is <code>O(n)</code>.</p>

<p>See more about Skiplist: <a href="https://en.wikipedia.org/wiki/Skip_list" target="_blank">https://en.wikipedia.org/wiki/Skip_list</a></p>

<p>Implement the <code>Skiplist</code> class:</p>

<ul>
	<li><code>Skiplist()</code> Initializes the object of the skiplist.</li>
	<li><code>bool search(int target)</code> Returns <code>true</code> if the integer <code>target</code> exists in the Skiplist or <code>false</code> otherwise.</li>
	<li><code>void add(int num)</code> Inserts the value <code>num</code> into the SkipList.</li>
	<li><code>bool erase(int num)</code> Removes the value <code>num</code> from the Skiplist and returns <code>true</code>. If <code>num</code> does not exist in the Skiplist, do nothing and return <code>false</code>. If there exist multiple <code>num</code> values, removing any one of them is fine.</li>
</ul>

<p>Note that duplicates may exist in the Skiplist, your code needs to handle this situation.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input</strong>
[&quot;Skiplist&quot;, &quot;add&quot;, &quot;add&quot;, &quot;add&quot;, &quot;search&quot;, &quot;add&quot;, &quot;search&quot;, &quot;erase&quot;, &quot;erase&quot;, &quot;search&quot;]
[[], [1], [2], [3], [0], [4], [1], [0], [1], [1]]
<strong>Output</strong>
[null, null, null, null, false, null, true, false, true, false]

<strong>Explanation</strong>
Skiplist skiplist = new Skiplist();
skiplist.add(1);
skiplist.add(2);
skiplist.add(3);
skiplist.search(0); // return False
skiplist.add(4);
skiplist.search(1); // return True
skiplist.erase(0);  // return False, 0 is not in skiplist.
skiplist.erase(1);  // return True
skiplist.search(1); // return False, 1 has already been erased.</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>0 &lt;= num, target &lt;= 2 * 10<sup>4</sup></code></li>
	<li>At most <code>5 * 10<sup>4</sup></code> calls will be made to <code>search</code>, <code>add</code>, and <code>erase</code>.</li>
</ul>

['design-hashset', 'design-hashmap', 'design-linked-list']
[]
[{"value": "cpp", "text": "C++", "defaultCode": "class Skiplist {\npublic:\n    Skiplist() {\n        \n    }\n    \n    bool search(int target) {\n        \n    }\n    \n    void add(int num) {\n        \n    }\n    \n    bool erase(int num) {\n        \n    }\n};\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * Skiplist* obj = new Skiplist();\n * bool param_1 = obj->search(target);\n * obj->add(num);\n * bool param_3 = obj->erase(num);\n */"}, {"value": "java", "text": "Java", "defaultCode": "class Skiplist {\n\n    public Skiplist() {\n        \n    }\n    \n    public boolean search(int target) {\n        \n    }\n    \n    public void add(int num) {\n        \n    }\n    \n    public boolean erase(int num) {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * Skiplist obj = new Skiplist();\n * boolean param_1 = obj.search(target);\n * obj.add(num);\n * boolean param_3 = obj.erase(num);\n */"}, {"value": "python", "text": "Python", "defaultCode": "class Skiplist(object):\n\n    def __init__(self):\n        \n\n    def search(self, target):\n        \"\"\"\n        :type target: int\n        :rtype: bool\n        \"\"\"\n        \n\n    def add(self, num):\n        \"\"\"\n        :type num: int\n        :rtype: None\n        \"\"\"\n        \n\n    def erase(self, num):\n        \"\"\"\n        :type num: int\n        :rtype: bool\n        \"\"\"\n        \n\n\n# Your Skiplist object will be instantiated and called as such:\n# obj = Skiplist()\n# param_1 = obj.search(target)\n# obj.add(num)\n# param_3 = obj.erase(num)"}, {"value": "python3", "text": "Python3", "defaultCode": "class Skiplist:\n\n    def __init__(self):\n        \n\n    def search(self, target: int) -> bool:\n        \n\n    def add(self, num: int) -> None:\n        \n\n    def erase(self, num: int) -> bool:\n        \n\n\n# Your Skiplist object will be instantiated and called as such:\n# obj = Skiplist()\n# param_1 = obj.search(target)\n# obj.add(num)\n# param_3 = obj.erase(num)"}, {"value": "c", "text": "C", "defaultCode": "\n\n\ntypedef struct {\n    \n} Skiplist;\n\n\nSkiplist* skiplistCreate() {\n    \n}\n\nbool skiplistSearch(Skiplist* obj, int target) {\n    \n}\n\nvoid skiplistAdd(Skiplist* obj, int num) {\n    \n}\n\nbool skiplistErase(Skiplist* obj, int num) {\n    \n}\n\nvoid skiplistFree(Skiplist* obj) {\n    \n}\n\n/**\n * Your Skiplist struct will be instantiated and called as such:\n * Skiplist* obj = skiplistCreate();\n * bool param_1 = skiplistSearch(obj, target);\n \n * skiplistAdd(obj, num);\n \n * bool param_3 = skiplistErase(obj, num);\n \n * skiplistFree(obj);\n*/"}, {"value": "csharp", "text": "C#", "defaultCode": "public class Skiplist {\n\n    public Skiplist() {\n        \n    }\n    \n    public bool Search(int target) {\n        \n    }\n    \n    public void Add(int num) {\n        \n    }\n    \n    public bool Erase(int num) {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * Skiplist obj = new Skiplist();\n * bool param_1 = obj.Search(target);\n * obj.Add(num);\n * bool param_3 = obj.Erase(num);\n */"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "\nvar Skiplist = function() {\n    \n};\n\n/** \n * @param {number} target\n * @return {boolean}\n */\nSkiplist.prototype.search = function(target) {\n    \n};\n\n/** \n * @param {number} num\n * @return {void}\n */\nSkiplist.prototype.add = function(num) {\n    \n};\n\n/** \n * @param {number} num\n * @return {boolean}\n */\nSkiplist.prototype.erase = function(num) {\n    \n};\n\n/** \n * Your Skiplist object will be instantiated and called as such:\n * var obj = new Skiplist()\n * var param_1 = obj.search(target)\n * obj.add(num)\n * var param_3 = obj.erase(num)\n */"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "class Skiplist {\n    constructor() {\n        \n    }\n\n    search(target: number): boolean {\n        \n    }\n\n    add(num: number): void {\n        \n    }\n\n    erase(num: number): boolean {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * var obj = new Skiplist()\n * var param_1 = obj.search(target)\n * obj.add(num)\n * var param_3 = obj.erase(num)\n */"}, {"value": "php", "text": "PHP", "defaultCode": "class Skiplist {\n    /**\n     */\n    function __construct() {\n        \n    }\n  \n    /**\n     * @param Integer $target\n     * @return Boolean\n     */\n    function search($target) {\n        \n    }\n  \n    /**\n     * @param Integer $num\n     * @return NULL\n     */\n    function add($num) {\n        \n    }\n  \n    /**\n     * @param Integer $num\n     * @return Boolean\n     */\n    function erase($num) {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * $obj = Skiplist();\n * $ret_1 = $obj->search($target);\n * $obj->add($num);\n * $ret_3 = $obj->erase($num);\n */"}, {"value": "swift", "text": "Swift", "defaultCode": "\nclass Skiplist {\n\n    init() {\n        \n    }\n    \n    func search(_ target: Int) -> Bool {\n        \n    }\n    \n    func add(_ num: Int) {\n        \n    }\n    \n    func erase(_ num: Int) -> Bool {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * let obj = Skiplist()\n * let ret_1: Bool = obj.search(target)\n * obj.add(num)\n * let ret_3: Bool = obj.erase(num)\n */"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class Skiplist() {\n\n    fun search(target: Int): Boolean {\n        \n    }\n\n    fun add(num: Int) {\n        \n    }\n\n    fun erase(num: Int): Boolean {\n        \n    }\n\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * var obj = Skiplist()\n * var param_1 = obj.search(target)\n * obj.add(num)\n * var param_3 = obj.erase(num)\n */"}, {"value": "dart", "text": "Dart", "defaultCode": "class Skiplist {\n\n  Skiplist() {\n    \n  }\n  \n  bool search(int target) {\n    \n  }\n  \n  void add(int num) {\n    \n  }\n  \n  bool erase(int num) {\n    \n  }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * Skiplist obj = Skiplist();\n * bool param1 = obj.search(target);\n * obj.add(num);\n * bool param3 = obj.erase(num);\n */"}, {"value": "golang", "text": "Go", "defaultCode": "type Skiplist struct {\n    \n}\n\n\nfunc Constructor() Skiplist {\n    \n}\n\n\nfunc (this *Skiplist) Search(target int) bool {\n    \n}\n\n\nfunc (this *Skiplist) Add(num int)  {\n    \n}\n\n\nfunc (this *Skiplist) Erase(num int) bool {\n    \n}\n\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * obj := Constructor();\n * param_1 := obj.Search(target);\n * obj.Add(num);\n * param_3 := obj.Erase(num);\n */"}, {"value": "ruby", "text": "Ruby", "defaultCode": "class Skiplist\n    def initialize()\n        \n    end\n\n\n=begin\n    :type target: Integer\n    :rtype: Boolean\n=end\n    def search(target)\n        \n    end\n\n\n=begin\n    :type num: Integer\n    :rtype: Void\n=end\n    def add(num)\n        \n    end\n\n\n=begin\n    :type num: Integer\n    :rtype: Boolean\n=end\n    def erase(num)\n        \n    end\n\n\nend\n\n# Your Skiplist object will be instantiated and called as such:\n# obj = Skiplist.new()\n# param_1 = obj.search(target)\n# obj.add(num)\n# param_3 = obj.erase(num)"}, {"value": "scala", "text": "Scala", "defaultCode": "class Skiplist() {\n\n    def search(target: Int): Boolean = {\n        \n    }\n\n    def add(num: Int): Unit = {\n        \n    }\n\n    def erase(num: Int): Boolean = {\n        \n    }\n\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * val obj = new Skiplist()\n * val param_1 = obj.search(target)\n * obj.add(num)\n * val param_3 = obj.erase(num)\n */"}, {"value": "rust", "text": "Rust", "defaultCode": "struct Skiplist {\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 Skiplist {\n\n    fn new() -> Self {\n        \n    }\n    \n    fn search(&self, target: i32) -> bool {\n        \n    }\n    \n    fn add(&self, num: i32) {\n        \n    }\n    \n    fn erase(&self, num: i32) -> bool {\n        \n    }\n}\n\n/**\n * Your Skiplist object will be instantiated and called as such:\n * let obj = Skiplist::new();\n * let ret_1: bool = obj.search(target);\n * obj.add(num);\n * let ret_3: bool = obj.erase(num);\n */"}, {"value": "racket", "text": "Racket", "defaultCode": "(define skiplist%\n  (class object%\n    (super-new)\n    \n    (init-field)\n    \n    ; search : exact-integer? -> boolean?\n    (define/public (search target)\n      )\n    ; add : exact-integer? -> void?\n    (define/public (add num)\n      )\n    ; erase : exact-integer? -> boolean?\n    (define/public (erase num)\n      )))\n\n;; Your skiplist% object will be instantiated and called as such:\n;; (define obj (new skiplist%))\n;; (define param_1 (send obj search target))\n;; (send obj add num)\n;; (define param_3 (send obj erase num))"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec skiplist_init_() -> any().\nskiplist_init_() ->\n  .\n\n-spec skiplist_search(Target :: integer()) -> boolean().\nskiplist_search(Target) ->\n  .\n\n-spec skiplist_add(Num :: integer()) -> any().\nskiplist_add(Num) ->\n  .\n\n-spec skiplist_erase(Num :: integer()) -> boolean().\nskiplist_erase(Num) ->\n  .\n\n\n%% Your functions will be called as such:\n%% skiplist_init_(),\n%% Param_1 = skiplist_search(Target),\n%% skiplist_add(Num),\n%% Param_3 = skiplist_erase(Num),\n\n%% skiplist_init_ will be called before every test case, in which you can do some necessary initializations."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule Skiplist do\n  @spec init_() :: any\n  def init_() do\n    \n  end\n\n  @spec search(target :: integer) :: boolean\n  def search(target) do\n    \n  end\n\n  @spec add(num :: integer) :: any\n  def add(num) do\n    \n  end\n\n  @spec erase(num :: integer) :: boolean\n  def erase(num) do\n    \n  end\nend\n\n# Your functions will be called as such:\n# Skiplist.init_()\n# param_1 = Skiplist.search(target)\n# Skiplist.add(num)\n# param_3 = Skiplist.erase(num)\n\n# Skiplist.init_ will be called before every test case, in which you can do some necessary initializations."}]
{
  "classname": "Skiplist",
  "maxbytesperline": 160000,
  "constructor": {
    "params": []
  },
  "methods": [
    {
      "params": [
        {
          "type": "integer",
          "name": "target"
        }
      ],
      "name": "search",
      "return": {
        "type": "boolean"
      }
    },
    {
      "params": [
        {
          "type": "integer",
          "name": "num"
        }
      ],
      "name": "add",
      "return": {
        "type": "void"
      }
    },
    {
      "params": [
        {
          "type": "integer",
          "name": "num"
        }
      ],
      "name": "erase",
      "return": {
        "type": "boolean"
      }
    }
  ],
  "return": {
    "type": "boolean"
  },
  "systemdesign": true
}
{"cpp": ["C++", "<p>Compiled with <code> clang 19 </code> using the latest C++ 23 standard, and <code>libstdc++</code> provided by GCC 14.</p>\r\n\r\n<p>Your code is compiled with level two optimization (<code>-O2</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>"], "java": ["Java", "<p><code>OpenJDK 21</code>. Using compile arguments: <code>--enable-preview --release 21</code></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 2.7.18</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\">is not maintained anymore</a>. For the latest Python, please choose Python3 instead.</p>"], "c": ["C", "<p>Compiled with <code>gcc 14</code> using the gnu11 standard.</p>\r\n\r\n<p>Your code is compiled with level one optimization (<code>-O2</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://learn.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-13\" target=\"_blank\">C# 13</a> with .NET 9 runtime</p>"], "javascript": ["JavaScript", "<p><code>Node.js 22.14.0</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 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "ruby": ["Ruby", "<p><code>Ruby 3.2</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 6.0</code>.</p>\r\n\r\n<p>You may use the following packages:<br/>\r\n<a href=\"https://github.com/apple/swift-algorithms/tree/1.2.0\" target=\"_blank\">swift-algorithms 1.2.0</a><br/>\r\n<a href=\"https://github.com/apple/swift-collections/tree/1.1.4\" target=\"_blank\">swift-collections 1.1.4</a><br/>\r\n<a href=\"https://github.com/apple/swift-numerics/tree/1.0.2\" target=\"_blank\">swift-numerics 1.0.2</a></p>"], "golang": ["Go", "<p><code>Go 1.23</code></p>\r\n<p>Support <a href=\"https://pkg.go.dev/github.com/emirpasic/gods@v1.18.1\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods@v1.18.1</a> and <a href=\"https://pkg.go.dev/github.com/emirpasic/gods/v2@v2.0.0-alpha\" target=\"_blank\">https://pkg.go.dev/github.com/emirpasic/gods/v2@v2.0.0-alpha</a> library.</p>"], "python3": ["Python3", "<p><code>Python 3.11</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 3.3.1</code>.</p>"], "kotlin": ["Kotlin", "<p><code>Kotlin 2.1.10</code>.</p>"], "rust": ["Rust", "<p><code>Rust 1.85.0</code>. Your code will be compiled with <code>opt-level</code> 2.</p>\r\n\r\n<p>Supports <a href=\"https://crates.io/crates/rand\" target=\"_blank\">rand v0.8</a> and <a href=\"https://crates.io/crates/regex\" target=\"_blank\">regex\u00a0v1</a> and <a href=\"https://crates.io/crates/itertools\" target=\"_blank\">itertools\u00a0v0.14</a> from crates.io</p>"], "php": ["PHP", "<p><code>PHP 8.2</code>.</p>\r\n<p>With bcmath module</p>"], "typescript": ["Typescript", "<p><code>TypeScript 5.7.3, Node.js 22.14.0</code>.</p>\r\n\r\n<p>Compile Options: <code>--alwaysStrict --strictBindCallApply --strictFunctionTypes --target ES2024</code></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 6.3.2 version of <a href=\"https://github.com/datastructures-js/priority-queue/tree/v6.3.2\" target=\"_blank\">datastructures-js/priority-queue</a> and 4.2.3 version of <a href=\"https://github.com/datastructures-js/queue/tree/v4.2.3\" target=\"_blank\">datastructures-js/queue</a> and 1.0.4 version of <a href=\"https://github.com/datastructures-js/deque/tree/v1.0.4\" target=\"_blank\">datastructures-js/deque</a>.</p>"], "racket": ["Racket", "<p><a href=\"https://docs.racket-lang.org/guide/performance.html#%28tech._c%29\" target=\"_blank\">Racket CS</a> v8.15</p>\r\n\r\n<p>Using <code>#lang racket</code></p>\r\n\r\n<p>Required <code>data/gvector data/queue data/order data/heap</code> automatically for your convenience</p>"], "erlang": ["Erlang", "Erlang/OTP 26"], "elixir": ["Elixir", "Elixir 1.17 with Erlang/OTP 26"], "dart": ["Dart", "<p>Dart 3.2. You may use package <a href=\"https://pub.dev/packages/collection/versions/1.18.0\" target=\"_blank\">collection</a></p>\r\n\r\n<p>Your code will be run directly without compiling</p>"]}
['Linked List', 'Design']