{ "data": { "question": { "questionId": "1359", "questionFrontendId": "1238", "boundTopicId": null, "title": "Circular Permutation in Binary Representation", "titleSlug": "circular-permutation-in-binary-representation", "content": "<p>Given 2 integers <code>n</code> and <code>start</code>. Your task is return <strong>any</strong> permutation <code>p</code> of <code>(0,1,2.....,2^n -1) </code>such that :</p>\r\n\r\n<ul>\r\n\t<li><code>p[0] = start</code></li>\r\n\t<li><code>p[i]</code> and <code>p[i+1]</code> differ by only one bit in their binary representation.</li>\r\n\t<li><code>p[0]</code> and <code>p[2^n -1]</code> must also differ by only one bit in their binary representation.</li>\r\n</ul>\r\n\r\n<p> </p>\r\n<p><strong>Example 1:</strong></p>\r\n\r\n<pre>\r\n<strong>Input:</strong> n = 2, start = 3\r\n<strong>Output:</strong> [3,2,0,1]\r\n<strong>Explanation:</strong> The binary representation of the permutation is (11,10,00,01). \r\nAll the adjacent element differ by one bit. Another valid permutation is [3,1,0,2]\r\n</pre>\r\n\r\n<p><strong>Example 2:</strong></p>\r\n\r\n<pre>\r\n<strong>Input:</strong> n = 3, start = 2\r\n<strong>Output:</strong> [2,6,7,5,4,0,1,3]\r\n<strong>Explanation:</strong> The binary representation of the permutation is (010,110,111,101,100,000,001,011).\r\n</pre>\r\n\r\n<p> </p>\r\n<p><strong>Constraints:</strong></p>\r\n\r\n<ul>\r\n\t<li><code>1 <= n <= 16</code></li>\r\n\t<li><code>0 <= start < 2 ^ n</code></li>\r\n</ul>", "translatedTitle": null, "translatedContent": null, "isPaidOnly": false, "difficulty": "Medium", "likes": 234, "dislikes": 155, "isLiked": null, "similarQuestions": "[]", "exampleTestcases": "2\n3\n3\n2", "categoryTitle": "Algorithms", "contributors": [], "topicTags": [ { "name": "Math", "slug": "math", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Backtracking", "slug": "backtracking", "translatedName": null, "__typename": "TopicTagNode" }, { "name": "Bit Manipulation", "slug": "bit-manipulation", "translatedName": null, "__typename": "TopicTagNode" } ], "companyTagStats": null, "codeSnippets": [ { "lang": "C++", "langSlug": "cpp", "code": "class Solution {\r\npublic:\r\n vector<int> circularPermutation(int n, int start) {\r\n \r\n }\r\n};", "__typename": "CodeSnippetNode" }, { "lang": "Java", "langSlug": "java", "code": "class Solution {\r\n public List<Integer> circularPermutation(int n, int start) {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "Python", "langSlug": "python", "code": "class Solution(object):\r\n def circularPermutation(self, n, start):\r\n \"\"\"\r\n :type n: int\r\n :type start: int\r\n :rtype: List[int]\r\n \"\"\"", "__typename": "CodeSnippetNode" }, { "lang": "Python3", "langSlug": "python3", "code": "class Solution:\r\n def circularPermutation(self, n: int, start: int) -> List[int]:", "__typename": "CodeSnippetNode" }, { "lang": "C", "langSlug": "c", "code": "/**\r\n * Note: The returned array must be malloced, assume caller calls free().\r\n */\r\nint* circularPermutation(int n, int start, int* returnSize){\r\n\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "C#", "langSlug": "csharp", "code": "public class Solution {\r\n public IList<int> CircularPermutation(int n, int start) {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "JavaScript", "langSlug": "javascript", "code": "/**\r\n * @param {number} n\r\n * @param {number} start\r\n * @return {number[]}\r\n */\r\nvar circularPermutation = function(n, start) {\r\n \r\n};", "__typename": "CodeSnippetNode" }, { "lang": "Ruby", "langSlug": "ruby", "code": "# @param {Integer} n\r\n# @param {Integer} start\r\n# @return {Integer[]}\r\ndef circular_permutation(n, start)\r\n \r\nend", "__typename": "CodeSnippetNode" }, { "lang": "Swift", "langSlug": "swift", "code": "class Solution {\r\n func circularPermutation(_ n: Int, _ start: Int) -> [Int] {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "Go", "langSlug": "golang", "code": "func circularPermutation(n int, start int) []int {\r\n \r\n}", "__typename": "CodeSnippetNode" }, { "lang": "Scala", "langSlug": "scala", "code": "object Solution {\r\n def circularPermutation(n: Int, start: Int): List[Int] = {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "Kotlin", "langSlug": "kotlin", "code": "class Solution {\r\n fun circularPermutation(n: Int, start: Int): List<Int> {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "Rust", "langSlug": "rust", "code": "impl Solution {\r\n pub fn circular_permutation(n: i32, start: i32) -> Vec<i32> {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "PHP", "langSlug": "php", "code": "class Solution {\r\n\r\n /**\r\n * @param Integer $n\r\n * @param Integer $start\r\n * @return Integer[]\r\n */\r\n function circularPermutation($n, $start) {\r\n \r\n }\r\n}", "__typename": "CodeSnippetNode" }, { "lang": "TypeScript", "langSlug": "typescript", "code": "function circularPermutation(n: number, start: number): number[] {\r\n\r\n};", "__typename": "CodeSnippetNode" } ], "stats": "{\"totalAccepted\": \"11.9K\", \"totalSubmission\": \"17.6K\", \"totalAcceptedRaw\": 11944, \"totalSubmissionRaw\": 17575, \"acRate\": \"68.0%\"}", "hints": [ "Use gray code to generate a n-bit sequence.", "Rotate the sequence such that its first element is start." ], "solution": null, "status": null, "sampleTestCase": "2\n3", "metaData": "{\n \"name\": \"circularPermutation\",\n \"params\": [\n {\n \"name\": \"n\",\n \"type\": \"integer\"\n },\n {\n \"type\": \"integer\",\n \"name\": \"start\"\n }\n ],\n \"return\": {\n \"type\": \"list<integer>\"\n }\n}", "judgerAvailable": true, "judgeType": "large", "mysqlSchemas": [], "enableRunCode": true, "enableTestMode": false, "enableDebugger": true, "envInfo": "{\"cpp\": [\"C++\", \"<p>Compiled with <code> clang 11 </code> using the latest C++ 17 standard.</p>\\r\\n\\r\\n<p>Your code is compiled with level two optimization (<code>-O2</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>\"], \"java\": [\"Java\", \"<p><code> OpenJDK 17 </code>. Java 8 features such as lambda expressions and stream API can be used. </p>\\r\\n\\r\\n<p>Most standard library headers are already included automatically for your convenience.</p>\\r\\n<p>Includes <code>Pair</code> class from https://docs.oracle.com/javase/8/javafx/api/javafx/util/Pair.html.</p>\"], \"python\": [\"Python\", \"<p><code>Python 2.7.12</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/2/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/2/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/2/library/collections.html\\\" target=\\\"_blank\\\">collections</a>. If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\\r\\n\\r\\n<p>Note that Python 2.7 <a href=\\\"https://www.python.org/dev/peps/pep-0373/\\\" target=\\\"_blank\\\">will not be maintained past 2020</a>. 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. Adding an item to a hash.</b>\\r\\n<pre>\\r\\nstruct hash_entry {\\r\\n int id; /* we'll use this field as the key */\\r\\n char name[10];\\r\\n UT_hash_handle hh; /* makes this structure hashable */\\r\\n};\\r\\n\\r\\nstruct hash_entry *users = NULL;\\r\\n\\r\\nvoid add_user(struct hash_entry *s) {\\r\\n HASH_ADD_INT(users, id, s);\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>2. Looking up an item in a hash:</b>\\r\\n<pre>\\r\\nstruct hash_entry *find_user(int user_id) {\\r\\n struct hash_entry *s;\\r\\n HASH_FIND_INT(users, &user_id, s);\\r\\n return s;\\r\\n}\\r\\n</pre>\\r\\n</p>\\r\\n\\r\\n<p><b>3. 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If you need more libraries, you can import it yourself.</p>\\r\\n\\r\\n<p>For Map/TreeMap data structure, you may use <a href=\\\"http://www.grantjenks.com/docs/sortedcontainers/\\\" target=\\\"_blank\\\">sortedcontainers</a> library.</p>\"], \"scala\": [\"Scala\", \"<p><code>Scala 2.13.7</code>.</p>\"], \"kotlin\": [\"Kotlin\", \"<p><code>Kotlin 1.3.10</code>.</p>\"], \"rust\": [\"Rust\", \"<p><code>Rust 1.58.1</code></p>\\r\\n\\r\\n<p>Supports <a href=\\\"https://crates.io/crates/rand\\\" target=\\\"_blank\\\">rand </a> v0.6\\u00a0from crates.io</p>\"], \"php\": [\"PHP\", \"<p><code>PHP 8.1</code>.</p>\\r\\n<p>With bcmath module</p>\"], \"typescript\": [\"Typescript\", \"<p><code>TypeScript 4.5.4, Node.js 16.13.2</code>.</p>\\r\\n\\r\\n<p>Your code is run with <code>--harmony</code> flag, enabling <a href=\\\"http://node.green/\\\" target=\\\"_blank\\\">new ES2020 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\"]}", "libraryUrl": null, "adminUrl": null, "challengeQuestion": null, "__typename": "QuestionNode" } } }