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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> </p>\n<p><strong class=\"example\">Example 1:</strong></p>\n\n<pre>\n<strong>Input</strong>\n["Solution", "pick", "pick", "pick", "pick", "pick", "pick", "pick"]\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> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= n <= 10<sup>9</sup></code></li>\n\t<li><code>0 <= blacklist.length <= min(10<sup>5</sup>, n - 1)</code></li>\n\t<li><code>0 <= blacklist[i] < 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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"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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"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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"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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"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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"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 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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"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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"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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"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": "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\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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"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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