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"title": "Shuffle an Array",
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"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> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n["Solution", "shuffle", "reset", "shuffle"]\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> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= nums.length <= 200</code></li>\n\t<li><code>-10<sup>6</sup> <= nums[i] <= 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>5 * 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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"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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"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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"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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"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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"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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"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 */",
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"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 */",
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"lang": "Ruby",
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"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()",
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"lang": "Swift",
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"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",
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"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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"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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"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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"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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"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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"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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"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": "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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