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"title": "Find Missing Observations",
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"content": "<p>You have observations of <code>n + m</code> <strong>6-sided</strong> dice rolls with each face numbered from <code>1</code> to <code>6</code>. <code>n</code> of the observations went missing, and you only have the observations of <code>m</code> rolls. Fortunately, you have also calculated the <strong>average value</strong> of the <code>n + m</code> rolls.</p>\n\n<p>You are given an integer array <code>rolls</code> of length <code>m</code> where <code>rolls[i]</code> is the value of the <code>i<sup>th</sup></code> observation. You are also given the two integers <code>mean</code> and <code>n</code>.</p>\n\n<p>Return <em>an array of length </em><code>n</code><em> containing the missing observations such that the <strong>average value </strong>of the </em><code>n + m</code><em> rolls is <strong>exactly</strong> </em><code>mean</code>. If there are multiple valid answers, return <em>any of them</em>. If no such array exists, return <em>an empty array</em>.</p>\n\n<p>The <strong>average value</strong> of a set of <code>k</code> numbers is the sum of the numbers divided by <code>k</code>.</p>\n\n<p>Note that <code>mean</code> is an integer, so the sum of the <code>n + m</code> rolls should be divisible by <code>n + m</code>.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n\n<pre>\n<strong>Input:</strong> rolls = [3,2,4,3], mean = 4, n = 2\n<strong>Output:</strong> [6,6]\n<strong>Explanation:</strong> The mean of all n + m rolls is (3 + 2 + 4 + 3 + 6 + 6) / 6 = 4.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n\n<pre>\n<strong>Input:</strong> rolls = [1,5,6], mean = 3, n = 4\n<strong>Output:</strong> [2,3,2,2]\n<strong>Explanation:</strong> The mean of all n + m rolls is (1 + 5 + 6 + 2 + 3 + 2 + 2) / 7 = 3.\n</pre>\n\n<p><strong>Example 3:</strong></p>\n\n<pre>\n<strong>Input:</strong> rolls = [1,2,3,4], mean = 6, n = 4\n<strong>Output:</strong> []\n<strong>Explanation:</strong> It is impossible for the mean to be 6 no matter what the 4 missing rolls are.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>m == rolls.length</code></li>\n\t<li><code>1 <= n, m <= 10<sup>5</sup></code></li>\n\t<li><code>1 <= rolls[i], mean <= 6</code></li>\n</ul>\n",
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"lang": "C++",
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"code": "class Solution {\npublic:\n vector<int> missingRolls(vector<int>& rolls, int mean, int n) {\n \n }\n};",
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"code": "class Solution {\n public int[] missingRolls(int[] rolls, int mean, int n) {\n \n }\n}",
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"lang": "Python",
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"code": "class Solution(object):\n def missingRolls(self, rolls, mean, n):\n \"\"\"\n :type rolls: List[int]\n :type mean: int\n :type n: int\n :rtype: List[int]\n \"\"\"\n ",
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"code": "class Solution:\n def missingRolls(self, rolls: List[int], mean: int, n: int) -> List[int]:\n ",
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"lang": "C",
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"code": "\n\n/**\n * Note: The returned array must be malloced, assume caller calls free().\n */\nint* missingRolls(int* rolls, int rollsSize, int mean, int n, int* returnSize){\n\n}",
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"code": "public class Solution {\n public int[] MissingRolls(int[] rolls, int mean, int n) {\n \n }\n}",
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"code": "/**\n * @param {number[]} rolls\n * @param {number} mean\n * @param {number} n\n * @return {number[]}\n */\nvar missingRolls = function(rolls, mean, n) {\n \n};",
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"code": "# @param {Integer[]} rolls\n# @param {Integer} mean\n# @param {Integer} n\n# @return {Integer[]}\ndef missing_rolls(rolls, mean, n)\n \nend",
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"lang": "Swift",
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"code": "class Solution {\n func missingRolls(_ rolls: [Int], _ mean: Int, _ n: Int) -> [Int] {\n \n }\n}",
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"lang": "Go",
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"code": "func missingRolls(rolls []int, mean int, n int) []int {\n \n}",
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"lang": "Scala",
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"code": "object Solution {\n def missingRolls(rolls: Array[Int], mean: Int, n: Int): Array[Int] = {\n \n }\n}",
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"lang": "Kotlin",
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"code": "class Solution {\n fun missingRolls(rolls: IntArray, mean: Int, n: Int): IntArray {\n \n }\n}",
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"lang": "Rust",
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"code": "impl Solution {\n pub fn missing_rolls(rolls: Vec<i32>, mean: i32, n: i32) -> Vec<i32> {\n \n }\n}",
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"lang": "PHP",
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"code": "class Solution {\n\n /**\n * @param Integer[] $rolls\n * @param Integer $mean\n * @param Integer $n\n * @return Integer[]\n */\n function missingRolls($rolls, $mean, $n) {\n \n }\n}",
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"code": "function missingRolls(rolls: number[], mean: number, n: number): number[] {\n\n};",
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"code": "(define/contract (missing-rolls rolls mean n)\n (-> (listof exact-integer?) exact-integer? exact-integer? (listof exact-integer?))\n\n )",
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"lang": "Erlang",
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"code": "-spec missing_rolls(Rolls :: [integer()], Mean :: integer(), N :: integer()) -> [integer()].\nmissing_rolls(Rolls, Mean, N) ->\n .",
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"lang": "Elixir",
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"code": "defmodule Solution do\n @spec missing_rolls(rolls :: [integer], mean :: integer, n :: integer) :: [integer]\n def missing_rolls(rolls, mean, n) do\n\n end\nend",
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"hints": [
"What should the sum of the n rolls be?",
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