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            "questionId": "384",
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            "title": "Shuffle an Array",
            "titleSlug": "shuffle-an-array",
            "content": "<p>Given an integer array <code>nums</code>, design an algorithm to randomly shuffle the array. All permutations of the array should be <strong>equally likely</strong> as a result of the shuffling.</p>\n\n<p>Implement the <code>Solution</code> class:</p>\n\n<ul>\n\t<li><code>Solution(int[] nums)</code> Initializes the object with the integer array <code>nums</code>.</li>\n\t<li><code>int[] reset()</code> Resets the array to its original configuration and returns it.</li>\n\t<li><code>int[] shuffle()</code> Returns a random shuffling of the array.</li>\n</ul>\n\n<p>&nbsp;</p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n[&quot;Solution&quot;, &quot;shuffle&quot;, &quot;reset&quot;, &quot;shuffle&quot;]\n[[[1, 2, 3]], [], [], []]\n<strong>Output</strong>\n[null, [3, 1, 2], [1, 2, 3], [1, 3, 2]]\n\n<strong>Explanation</strong>\nSolution solution = new Solution([1, 2, 3]);\nsolution.shuffle();    // Shuffle the array [1,2,3] and return its result.\n                       // Any permutation of [1,2,3] must be equally likely to be returned.\n                       // Example: return [3, 1, 2]\nsolution.reset();      // Resets the array back to its original configuration [1,2,3]. Return [1, 2, 3]\nsolution.shuffle();    // Returns the random shuffling of array [1,2,3]. Example: return [1, 3, 2]\n\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= nums.length &lt;= 50</code></li>\n\t<li><code>-10<sup>6</sup> &lt;= nums[i] &lt;= 10<sup>6</sup></code></li>\n\t<li>All the elements of <code>nums</code> are <strong>unique</strong>.</li>\n\t<li>At most <code>10<sup>4</sup></code> calls <strong>in total</strong> will be made to <code>reset</code> and <code>shuffle</code>.</li>\n</ul>\n",
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            "categoryTitle": "Algorithms",
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                    "lang": "C++",
                    "langSlug": "cpp",
                    "code": "class Solution {\npublic:\n    Solution(vector<int>& nums) {\n        \n    }\n    \n    vector<int> reset() {\n        \n    }\n    \n    vector<int> shuffle() {\n        \n    }\n};\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution* obj = new Solution(nums);\n * vector<int> param_1 = obj->reset();\n * vector<int> param_2 = obj->shuffle();\n */",
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                    "lang": "Java",
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                    "code": "class Solution {\n\n    public Solution(int[] nums) {\n        \n    }\n    \n    public int[] reset() {\n        \n    }\n    \n    public int[] shuffle() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution obj = new Solution(nums);\n * int[] param_1 = obj.reset();\n * int[] param_2 = obj.shuffle();\n */",
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                    "lang": "Python",
                    "langSlug": "python",
                    "code": "class Solution(object):\n\n    def __init__(self, nums):\n        \"\"\"\n        :type nums: List[int]\n        \"\"\"\n        \n\n    def reset(self):\n        \"\"\"\n        :rtype: List[int]\n        \"\"\"\n        \n\n    def shuffle(self):\n        \"\"\"\n        :rtype: List[int]\n        \"\"\"\n        \n\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution(nums)\n# param_1 = obj.reset()\n# param_2 = obj.shuffle()",
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                    "lang": "Python3",
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                    "code": "class Solution:\n\n    def __init__(self, nums: List[int]):\n        \n\n    def reset(self) -> List[int]:\n        \n\n    def shuffle(self) -> List[int]:\n        \n\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution(nums)\n# param_1 = obj.reset()\n# param_2 = obj.shuffle()",
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                {
                    "lang": "C",
                    "langSlug": "c",
                    "code": "\n\n\ntypedef struct {\n    \n} Solution;\n\n\nSolution* solutionCreate(int* nums, int numsSize) {\n    \n}\n\nint* solutionReset(Solution* obj, int* retSize) {\n  \n}\n\nint* solutionShuffle(Solution* obj, int* retSize) {\n  \n}\n\nvoid solutionFree(Solution* obj) {\n    \n}\n\n/**\n * Your Solution struct will be instantiated and called as such:\n * Solution* obj = solutionCreate(nums, numsSize);\n * int* param_1 = solutionReset(obj, retSize);\n \n * int* param_2 = solutionShuffle(obj, retSize);\n \n * solutionFree(obj);\n*/",
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                    "lang": "C#",
                    "langSlug": "csharp",
                    "code": "public class Solution {\n\n    public Solution(int[] nums) {\n        \n    }\n    \n    public int[] Reset() {\n        \n    }\n    \n    public int[] Shuffle() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution obj = new Solution(nums);\n * int[] param_1 = obj.Reset();\n * int[] param_2 = obj.Shuffle();\n */",
                    "__typename": "CodeSnippetNode"
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                    "lang": "JavaScript",
                    "langSlug": "javascript",
                    "code": "/**\n * @param {number[]} nums\n */\nvar Solution = function(nums) {\n    \n};\n\n/**\n * @return {number[]}\n */\nSolution.prototype.reset = function() {\n    \n};\n\n/**\n * @return {number[]}\n */\nSolution.prototype.shuffle = function() {\n    \n};\n\n/** \n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(nums)\n * var param_1 = obj.reset()\n * var param_2 = obj.shuffle()\n */",
                    "__typename": "CodeSnippetNode"
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                    "lang": "Ruby",
                    "langSlug": "ruby",
                    "code": "class Solution\n\n=begin\n    :type nums: Integer[]\n=end\n    def initialize(nums)\n        \n    end\n\n\n=begin\n    :rtype: Integer[]\n=end\n    def reset()\n        \n    end\n\n\n=begin\n    :rtype: Integer[]\n=end\n    def shuffle()\n        \n    end\n\n\nend\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution.new(nums)\n# param_1 = obj.reset()\n# param_2 = obj.shuffle()",
                    "__typename": "CodeSnippetNode"
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                    "lang": "Swift",
                    "langSlug": "swift",
                    "code": "\nclass Solution {\n\n    init(_ nums: [Int]) {\n        \n    }\n    \n    func reset() -> [Int] {\n        \n    }\n    \n    func shuffle() -> [Int] {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * let obj = Solution(nums)\n * let ret_1: [Int] = obj.reset()\n * let ret_2: [Int] = obj.shuffle()\n */",
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                {
                    "lang": "Go",
                    "langSlug": "golang",
                    "code": "type Solution struct {\n    \n}\n\n\nfunc Constructor(nums []int) Solution {\n    \n}\n\n\nfunc (this *Solution) Reset() []int {\n    \n}\n\n\nfunc (this *Solution) Shuffle() []int {\n    \n}\n\n\n/**\n * Your Solution object will be instantiated and called as such:\n * obj := Constructor(nums);\n * param_1 := obj.Reset();\n * param_2 := obj.Shuffle();\n */",
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                    "lang": "Scala",
                    "langSlug": "scala",
                    "code": "class Solution(_nums: Array[Int]) {\n\n    def reset(): Array[Int] = {\n        \n    }\n\n    def shuffle(): Array[Int] = {\n        \n    }\n\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(nums)\n * var param_1 = obj.reset()\n * var param_2 = obj.shuffle()\n */",
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                    "lang": "Kotlin",
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                    "code": "class Solution(nums: IntArray) {\n\n    fun reset(): IntArray {\n        \n    }\n\n    fun shuffle(): IntArray {\n        \n    }\n\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = Solution(nums)\n * var param_1 = obj.reset()\n * var param_2 = obj.shuffle()\n */",
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                    "lang": "Rust",
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                    "code": "struct Solution {\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 Solution {\n\n    fn new(nums: Vec<i32>) -> Self {\n        \n    }\n    \n    fn reset(&self) -> Vec<i32> {\n        \n    }\n    \n    fn shuffle(&self) -> Vec<i32> {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * let obj = Solution::new(nums);\n * let ret_1: Vec<i32> = obj.reset();\n * let ret_2: Vec<i32> = obj.shuffle();\n */",
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                    "lang": "PHP",
                    "langSlug": "php",
                    "code": "class Solution {\n    /**\n     * @param Integer[] $nums\n     */\n    function __construct($nums) {\n        \n    }\n  \n    /**\n     * @return Integer[]\n     */\n    function reset() {\n        \n    }\n  \n    /**\n     * @return Integer[]\n     */\n    function shuffle() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * $obj = Solution($nums);\n * $ret_1 = $obj->reset();\n * $ret_2 = $obj->shuffle();\n */",
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                    "lang": "TypeScript",
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                    "code": "class Solution {\n    constructor(nums: number[]) {\n\n    }\n\n    reset(): number[] {\n\n    }\n\n    shuffle(): number[] {\n\n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(nums)\n * var param_1 = obj.reset()\n * var param_2 = obj.shuffle()\n */",
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                    "lang": "Racket",
                    "langSlug": "racket",
                    "code": "(define solution%\n  (class object%\n    (super-new)\n    \n    ; nums : (listof exact-integer?)\n    (init-field\n      nums)\n    \n    ; reset : -> (listof exact-integer?)\n    (define/public (reset)\n\n      )\n    ; shuffle : -> (listof exact-integer?)\n    (define/public (shuffle)\n\n      )))\n\n;; Your solution% object will be instantiated and called as such:\n;; (define obj (new solution% [nums nums]))\n;; (define param_1 (send obj reset))\n;; (define param_2 (send obj shuffle))",
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                    "code": "-spec solution_init_(Nums :: [integer()]) -> any().\nsolution_init_(Nums) ->\n  .\n\n-spec solution_reset() -> [integer()].\nsolution_reset() ->\n  .\n\n-spec solution_shuffle() -> [integer()].\nsolution_shuffle() ->\n  .\n\n\n%% Your functions will be called as such:\n%% solution_init_(Nums),\n%% Param_1 = solution_reset(),\n%% Param_2 = solution_shuffle(),\n\n%% solution_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 Solution do\n  @spec init_(nums :: [integer]) :: any\n  def init_(nums) do\n\n  end\n\n  @spec reset() :: [integer]\n  def reset() do\n\n  end\n\n  @spec shuffle() :: [integer]\n  def shuffle() do\n\n  end\nend\n\n# Your functions will be called as such:\n# Solution.init_(nums)\n# param_1 = Solution.reset()\n# param_2 = Solution.shuffle()\n\n# Solution.init_ will be called before every test case, in which you can do some necessary initializations.",
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                "The solution expects that we always use the original array to shuffle() else some of the test cases fail. (Credits; @snehasingh31)"
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