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            "title": "RLE Iterator",
            "titleSlug": "rle-iterator",
            "content": "<p>We can use run-length encoding (i.e., <strong>RLE</strong>) to encode a sequence of integers. In a run-length encoded array of even length <code>encoding</code> (<strong>0-indexed</strong>), for all even <code>i</code>, <code>encoding[i]</code> tells us the number of times that the non-negative integer value <code>encoding[i + 1]</code> is repeated in the sequence.</p>\n\n<ul>\n\t<li>For example, the sequence <code>arr = [8,8,8,5,5]</code> can be encoded to be <code>encoding = [3,8,2,5]</code>. <code>encoding = [3,8,0,9,2,5]</code> and <code>encoding = [2,8,1,8,2,5]</code> are also valid <strong>RLE</strong> of <code>arr</code>.</li>\n</ul>\n\n<p>Given a run-length encoded array, design an iterator that iterates through it.</p>\n\n<p>Implement the <code>RLEIterator</code> class:</p>\n\n<ul>\n\t<li><code>RLEIterator(int[] encoded)</code> Initializes the object with the encoded array <code>encoded</code>.</li>\n\t<li><code>int next(int n)</code> Exhausts the next <code>n</code> elements and returns the last element exhausted in this way. If there is no element left to exhaust, return <code>-1</code> instead.</li>\n</ul>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n[&quot;RLEIterator&quot;, &quot;next&quot;, &quot;next&quot;, &quot;next&quot;, &quot;next&quot;]\n[[[3, 8, 0, 9, 2, 5]], [2], [1], [1], [2]]\n<strong>Output</strong>\n[null, 8, 8, 5, -1]\n\n<strong>Explanation</strong>\nRLEIterator rLEIterator = new RLEIterator([3, 8, 0, 9, 2, 5]); // This maps to the sequence [8,8,8,5,5].\nrLEIterator.next(2); // exhausts 2 terms of the sequence, returning 8. The remaining sequence is now [8, 5, 5].\nrLEIterator.next(1); // exhausts 1 term of the sequence, returning 8. The remaining sequence is now [5, 5].\nrLEIterator.next(1); // exhausts 1 term of the sequence, returning 5. The remaining sequence is now [5].\nrLEIterator.next(2); // exhausts 2 terms, returning -1. This is because the first term exhausted was 5,\nbut the second term did not exist. Since the last term exhausted does not exist, we return -1.\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>2 &lt;= encoding.length &lt;= 1000</code></li>\n\t<li><code>encoding.length</code> is even.</li>\n\t<li><code>0 &lt;= encoding[i] &lt;= 10<sup>9</sup></code></li>\n\t<li><code>1 &lt;= n &lt;= 10<sup>9</sup></code></li>\n\t<li>At most <code>1000</code> calls will be made to <code>next</code>.</li>\n</ul>\n",
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            "exampleTestcases": "[\"RLEIterator\",\"next\",\"next\",\"next\",\"next\"]\n[[[3,8,0,9,2,5]],[2],[1],[1],[2]]",
            "categoryTitle": "Algorithms",
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            "codeSnippets": [
                {
                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "class RLEIterator {\npublic:\n    RLEIterator(vector<int>& encoding) {\n        \n    }\n    \n    int next(int n) {\n        \n    }\n};\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * RLEIterator* obj = new RLEIterator(encoding);\n * int param_1 = obj->next(n);\n */",
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                    "lang": "Java",
                    "langSlug": "java",
                    "code": "class RLEIterator {\n\n    public RLEIterator(int[] encoding) {\n        \n    }\n    \n    public int next(int n) {\n        \n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * RLEIterator obj = new RLEIterator(encoding);\n * int param_1 = obj.next(n);\n */",
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                {
                    "lang": "Python",
                    "langSlug": "python",
                    "code": "class RLEIterator(object):\n\n    def __init__(self, encoding):\n        \"\"\"\n        :type encoding: List[int]\n        \"\"\"\n        \n\n    def next(self, n):\n        \"\"\"\n        :type n: int\n        :rtype: int\n        \"\"\"\n        \n\n\n# Your RLEIterator object will be instantiated and called as such:\n# obj = RLEIterator(encoding)\n# param_1 = obj.next(n)",
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                    "lang": "Python3",
                    "langSlug": "python3",
                    "code": "class RLEIterator:\n\n    def __init__(self, encoding: List[int]):\n        \n\n    def next(self, n: int) -> int:\n        \n\n\n# Your RLEIterator object will be instantiated and called as such:\n# obj = RLEIterator(encoding)\n# param_1 = obj.next(n)",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "C",
                    "langSlug": "c",
                    "code": "\n\n\ntypedef struct {\n    \n} RLEIterator;\n\n\nRLEIterator* rLEIteratorCreate(int* encoding, int encodingSize) {\n    \n}\n\nint rLEIteratorNext(RLEIterator* obj, int n) {\n  \n}\n\nvoid rLEIteratorFree(RLEIterator* obj) {\n    \n}\n\n/**\n * Your RLEIterator struct will be instantiated and called as such:\n * RLEIterator* obj = rLEIteratorCreate(encoding, encodingSize);\n * int param_1 = rLEIteratorNext(obj, n);\n \n * rLEIteratorFree(obj);\n*/",
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                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "public class RLEIterator {\n\n    public RLEIterator(int[] encoding) {\n        \n    }\n    \n    public int Next(int n) {\n        \n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * RLEIterator obj = new RLEIterator(encoding);\n * int param_1 = obj.Next(n);\n */",
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                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "/**\n * @param {number[]} encoding\n */\nvar RLEIterator = function(encoding) {\n    \n};\n\n/** \n * @param {number} n\n * @return {number}\n */\nRLEIterator.prototype.next = function(n) {\n    \n};\n\n/** \n * Your RLEIterator object will be instantiated and called as such:\n * var obj = new RLEIterator(encoding)\n * var param_1 = obj.next(n)\n */",
                    "__typename": "CodeSnippetNode"
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                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "class RLEIterator\n\n=begin\n    :type encoding: Integer[]\n=end\n    def initialize(encoding)\n        \n    end\n\n\n=begin\n    :type n: Integer\n    :rtype: Integer\n=end\n    def next(n)\n        \n    end\n\n\nend\n\n# Your RLEIterator object will be instantiated and called as such:\n# obj = RLEIterator.new(encoding)\n# param_1 = obj.next(n)",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Swift",
                    "langSlug": "swift",
                    "code": "\nclass RLEIterator {\n\n    init(_ encoding: [Int]) {\n        \n    }\n    \n    func next(_ n: Int) -> Int {\n        \n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * let obj = RLEIterator(encoding)\n * let ret_1: Int = obj.next(n)\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Go",
                    "langSlug": "golang",
                    "code": "type RLEIterator struct {\n    \n}\n\n\nfunc Constructor(encoding []int) RLEIterator {\n    \n}\n\n\nfunc (this *RLEIterator) Next(n int) int {\n    \n}\n\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * obj := Constructor(encoding);\n * param_1 := obj.Next(n);\n */",
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                    "lang": "Scala",
                    "langSlug": "scala",
                    "code": "class RLEIterator(_encoding: Array[Int]) {\n\n    def next(n: Int): Int = {\n        \n    }\n\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * var obj = new RLEIterator(encoding)\n * var param_1 = obj.next(n)\n */",
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                    "lang": "Kotlin",
                    "langSlug": "kotlin",
                    "code": "class RLEIterator(encoding: IntArray) {\n\n    fun next(n: Int): Int {\n        \n    }\n\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * var obj = RLEIterator(encoding)\n * var param_1 = obj.next(n)\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "Rust",
                    "langSlug": "rust",
                    "code": "struct RLEIterator {\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 RLEIterator {\n\n    fn new(encoding: Vec<i32>) -> Self {\n        \n    }\n    \n    fn next(&self, n: i32) -> i32 {\n        \n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * let obj = RLEIterator::new(encoding);\n * let ret_1: i32 = obj.next(n);\n */",
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                    "lang": "PHP",
                    "langSlug": "php",
                    "code": "class RLEIterator {\n    /**\n     * @param Integer[] $encoding\n     */\n    function __construct($encoding) {\n        \n    }\n  \n    /**\n     * @param Integer $n\n     * @return Integer\n     */\n    function next($n) {\n        \n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * $obj = RLEIterator($encoding);\n * $ret_1 = $obj->next($n);\n */",
                    "__typename": "CodeSnippetNode"
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                {
                    "lang": "TypeScript",
                    "langSlug": "typescript",
                    "code": "class RLEIterator {\n    constructor(encoding: number[]) {\n\n    }\n\n    next(n: number): number {\n\n    }\n}\n\n/**\n * Your RLEIterator object will be instantiated and called as such:\n * var obj = new RLEIterator(encoding)\n * var param_1 = obj.next(n)\n */",
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                    "lang": "Racket",
                    "langSlug": "racket",
                    "code": "(define rle-iterator%\n  (class object%\n    (super-new)\n\n    ; encoding : (listof exact-integer?)\n    (init-field\n      encoding)\n    \n    ; next : exact-integer? -> exact-integer?\n    (define/public (next n)\n\n      )))\n\n;; Your rle-iterator% object will be instantiated and called as such:\n;; (define obj (new rle-iterator% [encoding encoding]))\n;; (define param_1 (send obj next n))",
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                    "lang": "Erlang",
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                    "code": "-spec rle_iterator_init_(Encoding :: [integer()]) -> any().\nrle_iterator_init_(Encoding) ->\n  .\n\n-spec rle_iterator_next(N :: integer()) -> integer().\nrle_iterator_next(N) ->\n  .\n\n\n%% Your functions will be called as such:\n%% rle_iterator_init_(Encoding),\n%% Param_1 = rle_iterator_next(N),\n\n%% rle_iterator_init_ will be called before every test case, in which you can do some necessary initializations.",
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                    "lang": "Elixir",
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                    "code": "defmodule RLEIterator do\n  @spec init_(encoding :: [integer]) :: any\n  def init_(encoding) do\n\n  end\n\n  @spec next(n :: integer) :: integer\n  def next(n) do\n\n  end\nend\n\n# Your functions will be called as such:\n# RLEIterator.init_(encoding)\n# param_1 = RLEIterator.next(n)\n\n# RLEIterator.init_ will be called before every test case, in which you can do some necessary initializations.",
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