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            "title": "Random Pick with Blacklist",
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            "content": "<p>You are given an integer <code>n</code> and an array of <strong>unique</strong> integers <code>blacklist</code>. Design an algorithm to pick a random integer in the range <code>[0, n - 1]</code> that is <strong>not</strong> in <code>blacklist</code>. Any integer that is in the mentioned range and not in <code>blacklist</code> should be <strong>equally likely</strong> to be returned.</p>\n\n<p>Optimize your algorithm such that it minimizes the number of calls to the <strong>built-in</strong> random function of your language.</p>\n\n<p>Implement the <code>Solution</code> class:</p>\n\n<ul>\n\t<li><code>Solution(int n, int[] blacklist)</code> Initializes the object with the integer <code>n</code> and the blacklisted integers <code>blacklist</code>.</li>\n\t<li><code>int pick()</code> Returns a random integer in the range <code>[0, n - 1]</code> and not in <code>blacklist</code>.</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;pick&quot;, &quot;pick&quot;, &quot;pick&quot;, &quot;pick&quot;, &quot;pick&quot;, &quot;pick&quot;, &quot;pick&quot;]\n[[7, [2, 3, 5]], [], [], [], [], [], [], []]\n<strong>Output</strong>\n[null, 0, 4, 1, 6, 1, 0, 4]\n\n<strong>Explanation</strong>\nSolution solution = new Solution(7, [2, 3, 5]);\nsolution.pick(); // return 0, any integer from [0,1,4,6] should be ok. Note that for every call of pick,\n                 // 0, 1, 4, and 6 must be equally likely to be returned (i.e., with probability 1/4).\nsolution.pick(); // return 4\nsolution.pick(); // return 1\nsolution.pick(); // return 6\nsolution.pick(); // return 1\nsolution.pick(); // return 0\nsolution.pick(); // return 4\n</pre>\n\n<p>&nbsp;</p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 &lt;= n &lt;= 10<sup>9</sup></code></li>\n\t<li><code>0 &lt;= blacklist.length &lt;- min(10<sup>5</sup>, n - 1)</code></li>\n\t<li><code>0 &lt;= blacklist[i] &lt; n</code></li>\n\t<li>All the values of <code>blacklist</code> are <strong>unique</strong>.</li>\n\t<li>At most <code>2 * 10<sup>4</sup></code> calls will be made to <code>pick</code>.</li>\n</ul>\n",
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            "categoryTitle": "Algorithms",
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                    "lang": "C++",
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                    "code": "class Solution {\npublic:\n    Solution(int n, vector<int>& blacklist) {\n        \n    }\n    \n    int pick() {\n        \n    }\n};\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution* obj = new Solution(n, blacklist);\n * int param_1 = obj->pick();\n */",
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                    "lang": "Java",
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                    "code": "class Solution {\n\n    public Solution(int n, int[] blacklist) {\n        \n    }\n    \n    public int pick() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution obj = new Solution(n, blacklist);\n * int param_1 = obj.pick();\n */",
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                    "lang": "Python",
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                    "code": "class Solution(object):\n\n    def __init__(self, n, blacklist):\n        \"\"\"\n        :type n: int\n        :type blacklist: List[int]\n        \"\"\"\n        \n\n    def pick(self):\n        \"\"\"\n        :rtype: int\n        \"\"\"\n        \n\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution(n, blacklist)\n# param_1 = obj.pick()",
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                    "lang": "Python3",
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                    "code": "class Solution:\n\n    def __init__(self, n: int, blacklist: List[int]):\n        \n\n    def pick(self) -> int:\n        \n\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution(n, blacklist)\n# param_1 = obj.pick()",
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                    "lang": "C",
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                    "code": "\n\n\ntypedef struct {\n    \n} Solution;\n\n\nSolution* solutionCreate(int n, int* blacklist, int blacklistSize) {\n    \n}\n\nint solutionPick(Solution* obj) {\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(n, blacklist, blacklistSize);\n * int param_1 = solutionPick(obj);\n \n * solutionFree(obj);\n*/",
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                    "code": "public class Solution {\n\n    public Solution(int n, int[] blacklist) {\n        \n    }\n    \n    public int Pick() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * Solution obj = new Solution(n, blacklist);\n * int param_1 = obj.Pick();\n */",
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                    "code": "/**\n * @param {number} n\n * @param {number[]} blacklist\n */\nvar Solution = function(n, blacklist) {\n    \n};\n\n/**\n * @return {number}\n */\nSolution.prototype.pick = function() {\n    \n};\n\n/** \n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(n, blacklist)\n * var param_1 = obj.pick()\n */",
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                    "code": "class Solution\n\n=begin\n    :type n: Integer\n    :type blacklist: Integer[]\n=end\n    def initialize(n, blacklist)\n        \n    end\n\n\n=begin\n    :rtype: Integer\n=end\n    def pick()\n        \n    end\n\n\nend\n\n# Your Solution object will be instantiated and called as such:\n# obj = Solution.new(n, blacklist)\n# param_1 = obj.pick()",
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                    "lang": "Swift",
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                    "code": "\nclass Solution {\n\n    init(_ n: Int, _ blacklist: [Int]) {\n        \n    }\n    \n    func pick() -> Int {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * let obj = Solution(n, blacklist)\n * let ret_1: Int = obj.pick()\n */",
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                    "lang": "Go",
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                    "code": "type Solution struct {\n    \n}\n\n\nfunc Constructor(n int, blacklist []int) Solution {\n    \n}\n\n\nfunc (this *Solution) Pick() int {\n    \n}\n\n\n/**\n * Your Solution object will be instantiated and called as such:\n * obj := Constructor(n, blacklist);\n * param_1 := obj.Pick();\n */",
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                    "code": "class Solution(_n: Int, _blacklist: Array[Int]) {\n\n    def pick(): Int = {\n        \n    }\n\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(n, blacklist)\n * var param_1 = obj.pick()\n */",
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                    "code": "class Solution(n: Int, blacklist: IntArray) {\n\n    fun pick(): Int {\n        \n    }\n\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = Solution(n, blacklist)\n * var param_1 = obj.pick()\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(n: i32, blacklist: Vec<i32>) -> Self {\n        \n    }\n    \n    fn pick(&self) -> i32 {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * let obj = Solution::new(n, blacklist);\n * let ret_1: i32 = obj.pick();\n */",
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                    "code": "class Solution {\n    /**\n     * @param Integer $n\n     * @param Integer[] $blacklist\n     */\n    function __construct($n, $blacklist) {\n        \n    }\n  \n    /**\n     * @return Integer\n     */\n    function pick() {\n        \n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * $obj = Solution($n, $blacklist);\n * $ret_1 = $obj->pick();\n */",
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                    "lang": "TypeScript",
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                    "code": "class Solution {\n    constructor(n: number, blacklist: number[]) {\n\n    }\n\n    pick(): number {\n\n    }\n}\n\n/**\n * Your Solution object will be instantiated and called as such:\n * var obj = new Solution(n, blacklist)\n * var param_1 = obj.pick()\n */",
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For the latest Python, please choose Python3 instead.</p>\"], \"c\": [\"C\", \"<p>Compiled with <code>gcc 8.2</code> using the gnu99 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level one optimization (<code>-O1</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. 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