Finding MK Average
<p>You are given two integers, <code>m</code> and <code>k</code>, and a stream of integers. You are tasked to implement a data structure that calculates the <strong>MKAverage</strong> for the stream.</p>

<p>The <strong>MKAverage</strong> can be calculated using these steps:</p>

<ol>
	<li>If the number of the elements in the stream is less than <code>m</code> you should consider the <strong>MKAverage</strong> to be <code>-1</code>. Otherwise, copy the last <code>m</code> elements of the stream to a separate container.</li>
	<li>Remove the smallest <code>k</code> elements and the largest <code>k</code> elements from the container.</li>
	<li>Calculate the average value for the rest of the elements <strong>rounded down to the nearest integer</strong>.</li>
</ol>

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

<ul>
	<li><code>MKAverage(int m, int k)</code> Initializes the <strong>MKAverage</strong> object with an empty stream and the two integers <code>m</code> and <code>k</code>.</li>
	<li><code>void addElement(int num)</code> Inserts a new element <code>num</code> into the stream.</li>
	<li><code>int calculateMKAverage()</code> Calculates and returns the <strong>MKAverage</strong> for the current stream <strong>rounded down to the nearest integer</strong>.</li>
</ul>

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

<pre>
<strong>Input</strong>
[&quot;MKAverage&quot;, &quot;addElement&quot;, &quot;addElement&quot;, &quot;calculateMKAverage&quot;, &quot;addElement&quot;, &quot;calculateMKAverage&quot;, &quot;addElement&quot;, &quot;addElement&quot;, &quot;addElement&quot;, &quot;calculateMKAverage&quot;]
[[3, 1], [3], [1], [], [10], [], [5], [5], [5], []]
<strong>Output</strong>
[null, null, null, -1, null, 3, null, null, null, 5]

<strong>Explanation</strong>
<code>MKAverage obj = new MKAverage(3, 1); 
obj.addElement(3);        // current elements are [3]
obj.addElement(1);        // current elements are [3,1]
obj.calculateMKAverage(); // return -1, because m = 3 and only 2 elements exist.
obj.addElement(10);       // current elements are [3,1,10]
obj.calculateMKAverage(); // The last 3 elements are [3,1,10].
                          // After removing smallest and largest 1 element the container will be [3].
                          // The average of [3] equals 3/1 = 3, return 3
obj.addElement(5);        // current elements are [3,1,10,5]
obj.addElement(5);        // current elements are [3,1,10,5,5]
obj.addElement(5);        // current elements are [3,1,10,5,5,5]
obj.calculateMKAverage(); // The last 3 elements are [5,5,5].
                          // After removing smallest and largest 1 element the container will be [5].
                          // The average of [5] equals 5/1 = 5, return 5
</code></pre>

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

<ul>
	<li><code>3 &lt;= m &lt;= 10<sup>5</sup></code></li>
	<li><code>1 &lt;= k*2 &lt; m</code></li>
	<li><code>1 &lt;= num &lt;= 10<sup>5</sup></code></li>
	<li>At most <code>10<sup>5</sup></code> calls will be made to <code>addElement</code> and <code>calculateMKAverage</code>.</li>
</ul>

['find-median-from-data-stream', 'kth-largest-element-in-a-stream', 'sequentially-ordinal-rank-tracker']
[]
[{"value": "cpp", "text": "C++", "defaultCode": "class MKAverage {\npublic:\n    MKAverage(int m, int k) {\n        \n    }\n    \n    void addElement(int num) {\n        \n    }\n    \n    int calculateMKAverage() {\n        \n    }\n};\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * MKAverage* obj = new MKAverage(m, k);\n * obj->addElement(num);\n * int param_2 = obj->calculateMKAverage();\n */"}, {"value": "java", "text": "Java", "defaultCode": "class MKAverage {\n\n    public MKAverage(int m, int k) {\n        \n    }\n    \n    public void addElement(int num) {\n        \n    }\n    \n    public int calculateMKAverage() {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * MKAverage obj = new MKAverage(m, k);\n * obj.addElement(num);\n * int param_2 = obj.calculateMKAverage();\n */"}, {"value": "python", "text": "Python", "defaultCode": "class MKAverage(object):\n\n    def __init__(self, m, k):\n        \"\"\"\n        :type m: int\n        :type k: int\n        \"\"\"\n        \n\n    def addElement(self, num):\n        \"\"\"\n        :type num: int\n        :rtype: None\n        \"\"\"\n        \n\n    def calculateMKAverage(self):\n        \"\"\"\n        :rtype: int\n        \"\"\"\n        \n\n\n# Your MKAverage object will be instantiated and called as such:\n# obj = MKAverage(m, k)\n# obj.addElement(num)\n# param_2 = obj.calculateMKAverage()"}, {"value": "python3", "text": "Python3", "defaultCode": "class MKAverage:\n\n    def __init__(self, m: int, k: int):\n        \n\n    def addElement(self, num: int) -> None:\n        \n\n    def calculateMKAverage(self) -> int:\n        \n\n\n# Your MKAverage object will be instantiated and called as such:\n# obj = MKAverage(m, k)\n# obj.addElement(num)\n# param_2 = obj.calculateMKAverage()"}, {"value": "c", "text": "C", "defaultCode": "\n\n\ntypedef struct {\n    \n} MKAverage;\n\n\nMKAverage* mKAverageCreate(int m, int k) {\n    \n}\n\nvoid mKAverageAddElement(MKAverage* obj, int num) {\n    \n}\n\nint mKAverageCalculateMKAverage(MKAverage* obj) {\n    \n}\n\nvoid mKAverageFree(MKAverage* obj) {\n    \n}\n\n/**\n * Your MKAverage struct will be instantiated and called as such:\n * MKAverage* obj = mKAverageCreate(m, k);\n * mKAverageAddElement(obj, num);\n \n * int param_2 = mKAverageCalculateMKAverage(obj);\n \n * mKAverageFree(obj);\n*/"}, {"value": "csharp", "text": "C#", "defaultCode": "public class MKAverage {\n\n    public MKAverage(int m, int k) {\n        \n    }\n    \n    public void AddElement(int num) {\n        \n    }\n    \n    public int CalculateMKAverage() {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * MKAverage obj = new MKAverage(m, k);\n * obj.AddElement(num);\n * int param_2 = obj.CalculateMKAverage();\n */"}, {"value": "javascript", "text": "JavaScript", "defaultCode": "/**\n * @param {number} m\n * @param {number} k\n */\nvar MKAverage = function(m, k) {\n    \n};\n\n/** \n * @param {number} num\n * @return {void}\n */\nMKAverage.prototype.addElement = function(num) {\n    \n};\n\n/**\n * @return {number}\n */\nMKAverage.prototype.calculateMKAverage = function() {\n    \n};\n\n/** \n * Your MKAverage object will be instantiated and called as such:\n * var obj = new MKAverage(m, k)\n * obj.addElement(num)\n * var param_2 = obj.calculateMKAverage()\n */"}, {"value": "typescript", "text": "TypeScript", "defaultCode": "class MKAverage {\n    constructor(m: number, k: number) {\n        \n    }\n\n    addElement(num: number): void {\n        \n    }\n\n    calculateMKAverage(): number {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * var obj = new MKAverage(m, k)\n * obj.addElement(num)\n * var param_2 = obj.calculateMKAverage()\n */"}, {"value": "php", "text": "PHP", "defaultCode": "class MKAverage {\n    /**\n     * @param Integer $m\n     * @param Integer $k\n     */\n    function __construct($m, $k) {\n        \n    }\n  \n    /**\n     * @param Integer $num\n     * @return NULL\n     */\n    function addElement($num) {\n        \n    }\n  \n    /**\n     * @return Integer\n     */\n    function calculateMKAverage() {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * $obj = MKAverage($m, $k);\n * $obj->addElement($num);\n * $ret_2 = $obj->calculateMKAverage();\n */"}, {"value": "swift", "text": "Swift", "defaultCode": "\nclass MKAverage {\n\n    init(_ m: Int, _ k: Int) {\n        \n    }\n    \n    func addElement(_ num: Int) {\n        \n    }\n    \n    func calculateMKAverage() -> Int {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * let obj = MKAverage(m, k)\n * obj.addElement(num)\n * let ret_2: Int = obj.calculateMKAverage()\n */"}, {"value": "kotlin", "text": "Kotlin", "defaultCode": "class MKAverage(m: Int, k: Int) {\n\n    fun addElement(num: Int) {\n        \n    }\n\n    fun calculateMKAverage(): Int {\n        \n    }\n\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * var obj = MKAverage(m, k)\n * obj.addElement(num)\n * var param_2 = obj.calculateMKAverage()\n */"}, {"value": "dart", "text": "Dart", "defaultCode": "class MKAverage {\n\n  MKAverage(int m, int k) {\n    \n  }\n  \n  void addElement(int num) {\n    \n  }\n  \n  int calculateMKAverage() {\n    \n  }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * MKAverage obj = MKAverage(m, k);\n * obj.addElement(num);\n * int param2 = obj.calculateMKAverage();\n */"}, {"value": "golang", "text": "Go", "defaultCode": "type MKAverage struct {\n    \n}\n\n\nfunc Constructor(m int, k int) MKAverage {\n    \n}\n\n\nfunc (this *MKAverage) AddElement(num int)  {\n    \n}\n\n\nfunc (this *MKAverage) CalculateMKAverage() int {\n    \n}\n\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * obj := Constructor(m, k);\n * obj.AddElement(num);\n * param_2 := obj.CalculateMKAverage();\n */"}, {"value": "ruby", "text": "Ruby", "defaultCode": "class MKAverage\n\n=begin\n    :type m: Integer\n    :type k: Integer\n=end\n    def initialize(m, k)\n        \n    end\n\n\n=begin\n    :type num: Integer\n    :rtype: Void\n=end\n    def add_element(num)\n        \n    end\n\n\n=begin\n    :rtype: Integer\n=end\n    def calculate_mk_average()\n        \n    end\n\n\nend\n\n# Your MKAverage object will be instantiated and called as such:\n# obj = MKAverage.new(m, k)\n# obj.add_element(num)\n# param_2 = obj.calculate_mk_average()"}, {"value": "scala", "text": "Scala", "defaultCode": "class MKAverage(_m: Int, _k: Int) {\n\n    def addElement(num: Int): Unit = {\n        \n    }\n\n    def calculateMKAverage(): Int = {\n        \n    }\n\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * val obj = new MKAverage(m, k)\n * obj.addElement(num)\n * val param_2 = obj.calculateMKAverage()\n */"}, {"value": "rust", "text": "Rust", "defaultCode": "struct MKAverage {\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 MKAverage {\n\n    fn new(m: i32, k: i32) -> Self {\n        \n    }\n    \n    fn add_element(&self, num: i32) {\n        \n    }\n    \n    fn calculate_mk_average(&self) -> i32 {\n        \n    }\n}\n\n/**\n * Your MKAverage object will be instantiated and called as such:\n * let obj = MKAverage::new(m, k);\n * obj.add_element(num);\n * let ret_2: i32 = obj.calculate_mk_average();\n */"}, {"value": "racket", "text": "Racket", "defaultCode": "(define mk-average%\n  (class object%\n    (super-new)\n    \n    ; m : exact-integer?\n    ; k : exact-integer?\n    (init-field\n      m\n      k)\n    \n    ; add-element : exact-integer? -> void?\n    (define/public (add-element num)\n      )\n    ; calculate-mk-average : -> exact-integer?\n    (define/public (calculate-mk-average)\n      )))\n\n;; Your mk-average% object will be instantiated and called as such:\n;; (define obj (new mk-average% [m m] [k k]))\n;; (send obj add-element num)\n;; (define param_2 (send obj calculate-mk-average))"}, {"value": "erlang", "text": "Erlang", "defaultCode": "-spec mk_average_init_(M :: integer(), K :: integer()) -> any().\nmk_average_init_(M, K) ->\n  .\n\n-spec mk_average_add_element(Num :: integer()) -> any().\nmk_average_add_element(Num) ->\n  .\n\n-spec mk_average_calculate_mk_average() -> integer().\nmk_average_calculate_mk_average() ->\n  .\n\n\n%% Your functions will be called as such:\n%% mk_average_init_(M, K),\n%% mk_average_add_element(Num),\n%% Param_2 = mk_average_calculate_mk_average(),\n\n%% mk_average_init_ will be called before every test case, in which you can do some necessary initializations."}, {"value": "elixir", "text": "Elixir", "defaultCode": "defmodule MKAverage do\n  @spec init_(m :: integer, k :: integer) :: any\n  def init_(m, k) do\n    \n  end\n\n  @spec add_element(num :: integer) :: any\n  def add_element(num) do\n    \n  end\n\n  @spec calculate_mk_average() :: integer\n  def calculate_mk_average() do\n    \n  end\nend\n\n# Your functions will be called as such:\n# MKAverage.init_(m, k)\n# MKAverage.add_element(num)\n# param_2 = MKAverage.calculate_mk_average()\n\n# MKAverage.init_ will be called before every test case, in which you can do some necessary initializations."}]
{
  "classname": "MKAverage",
  "constructor": {
    "params": [
      {
        "name": "m",
        "type": "integer"
      },
      {
        "name": "k",
        "type": "integer"
      }
    ]
  },
  "methods": [
    {
      "params": [
        {
          "type": "integer",
          "name": "num"
        }
      ],
      "name": "addElement",
      "return": {
        "type": "void"
      }
    },
    {
      "params": [],
      "name": "calculateMKAverage",
      "return": {
        "type": "integer"
      }
    }
  ],
  "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>"]}
['Design', 'Queue', 'Heap (Priority Queue)', 'Data Stream', 'Ordered Set']