mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
synced 2025-01-11 02:58:13 +08:00
180 lines
18 KiB
JSON
180 lines
18 KiB
JSON
{
|
|
"data": {
|
|
"question": {
|
|
"questionId": "1431",
|
|
"questionFrontendId": "2192",
|
|
"boundTopicId": null,
|
|
"title": "All Ancestors of a Node in a Directed Acyclic Graph",
|
|
"titleSlug": "all-ancestors-of-a-node-in-a-directed-acyclic-graph",
|
|
"content": "<p>You are given a positive integer <code>n</code> representing the number of nodes of a <strong>Directed Acyclic Graph</strong> (DAG). The nodes are numbered from <code>0</code> to <code>n - 1</code> (<strong>inclusive</strong>).</p>\n\n<p>You are also given a 2D integer array <code>edges</code>, where <code>edges[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> denotes that there is a <strong>unidirectional</strong> edge from <code>from<sub>i</sub></code> to <code>to<sub>i</sub></code> in the graph.</p>\n\n<p>Return <em>a list</em> <code>answer</code><em>, where </em><code>answer[i]</code><em> is the <strong>list of ancestors</strong> of the</em> <code>i<sup>th</sup></code> <em>node, sorted in <strong>ascending order</strong></em>.</p>\n\n<p>A node <code>u</code> is an <strong>ancestor</strong> of another node <code>v</code> if <code>u</code> can reach <code>v</code> via a set of edges.</p>\n\n<p> </p>\n<p><strong>Example 1:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2019/12/12/e1.png\" style=\"width: 322px; height: 265px;\" />\n<pre>\n<strong>Input:</strong> n = 8, edgeList = [[0,3],[0,4],[1,3],[2,4],[2,7],[3,5],[3,6],[3,7],[4,6]]\n<strong>Output:</strong> [[],[],[],[0,1],[0,2],[0,1,3],[0,1,2,3,4],[0,1,2,3]]\n<strong>Explanation:</strong>\nThe above diagram represents the input graph.\n- Nodes 0, 1, and 2 do not have any ancestors.\n- Node 3 has two ancestors 0 and 1.\n- Node 4 has two ancestors 0 and 2.\n- Node 5 has three ancestors 0, 1, and 3.\n- Node 6 has five ancestors 0, 1, 2, 3, and 4.\n- Node 7 has four ancestors 0, 1, 2, and 3.\n</pre>\n\n<p><strong>Example 2:</strong></p>\n<img alt=\"\" src=\"https://assets.leetcode.com/uploads/2019/12/12/e2.png\" style=\"width: 343px; height: 299px;\" />\n<pre>\n<strong>Input:</strong> n = 5, edgeList = [[0,1],[0,2],[0,3],[0,4],[1,2],[1,3],[1,4],[2,3],[2,4],[3,4]]\n<strong>Output:</strong> [[],[0],[0,1],[0,1,2],[0,1,2,3]]\n<strong>Explanation:</strong>\nThe above diagram represents the input graph.\n- Node 0 does not have any ancestor.\n- Node 1 has one ancestor 0.\n- Node 2 has two ancestors 0 and 1.\n- Node 3 has three ancestors 0, 1, and 2.\n- Node 4 has four ancestors 0, 1, 2, and 3.\n</pre>\n\n<p> </p>\n<p><strong>Constraints:</strong></p>\n\n<ul>\n\t<li><code>1 <= n <= 1000</code></li>\n\t<li><code>0 <= edges.length <= min(2000, n * (n - 1) / 2)</code></li>\n\t<li><code>edges[i].length == 2</code></li>\n\t<li><code>0 <= from<sub>i</sub>, to<sub>i</sub> <= n - 1</code></li>\n\t<li><code>from<sub>i</sub> != to<sub>i</sub></code></li>\n\t<li>There are no duplicate edges.</li>\n\t<li>The graph is <strong>directed</strong> and <strong>acyclic</strong>.</li>\n</ul>\n",
|
|
"translatedTitle": null,
|
|
"translatedContent": null,
|
|
"isPaidOnly": false,
|
|
"difficulty": "Medium",
|
|
"likes": 357,
|
|
"dislikes": 4,
|
|
"isLiked": null,
|
|
"similarQuestions": "[{\"title\": \"Number of Restricted Paths From First to Last Node\", \"titleSlug\": \"number-of-restricted-paths-from-first-to-last-node\", \"difficulty\": \"Medium\", \"translatedTitle\": null}]",
|
|
"exampleTestcases": "8\n[[0,3],[0,4],[1,3],[2,4],[2,7],[3,5],[3,6],[3,7],[4,6]]\n5\n[[0,1],[0,2],[0,3],[0,4],[1,2],[1,3],[1,4],[2,3],[2,4],[3,4]]",
|
|
"categoryTitle": "Algorithms",
|
|
"contributors": [],
|
|
"topicTags": [
|
|
{
|
|
"name": "Depth-First Search",
|
|
"slug": "depth-first-search",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Breadth-First Search",
|
|
"slug": "breadth-first-search",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Graph",
|
|
"slug": "graph",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
},
|
|
{
|
|
"name": "Topological Sort",
|
|
"slug": "topological-sort",
|
|
"translatedName": null,
|
|
"__typename": "TopicTagNode"
|
|
}
|
|
],
|
|
"companyTagStats": null,
|
|
"codeSnippets": [
|
|
{
|
|
"lang": "C++",
|
|
"langSlug": "cpp",
|
|
"code": "class Solution {\npublic:\n vector<vector<int>> getAncestors(int n, vector<vector<int>>& edges) {\n \n }\n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Java",
|
|
"langSlug": "java",
|
|
"code": "class Solution {\n public List<List<Integer>> getAncestors(int n, int[][] edges) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Python",
|
|
"langSlug": "python",
|
|
"code": "class Solution(object):\n def getAncestors(self, n, edges):\n \"\"\"\n :type n: int\n :type edges: List[List[int]]\n :rtype: List[List[int]]\n \"\"\"\n ",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Python3",
|
|
"langSlug": "python3",
|
|
"code": "class Solution:\n def getAncestors(self, n: int, edges: List[List[int]]) -> List[List[int]]:\n ",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "C",
|
|
"langSlug": "c",
|
|
"code": "\n\n/**\n * Return an array of arrays of size *returnSize.\n * The sizes of the arrays are returned as *returnColumnSizes array.\n * Note: Both returned array and *columnSizes array must be malloced, assume caller calls free().\n */\nint** getAncestors(int n, int** edges, int edgesSize, int* edgesColSize, int* returnSize, int** returnColumnSizes){\n\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "C#",
|
|
"langSlug": "csharp",
|
|
"code": "public class Solution {\n public IList<IList<int>> GetAncestors(int n, int[][] edges) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "JavaScript",
|
|
"langSlug": "javascript",
|
|
"code": "/**\n * @param {number} n\n * @param {number[][]} edges\n * @return {number[][]}\n */\nvar getAncestors = function(n, edges) {\n \n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Ruby",
|
|
"langSlug": "ruby",
|
|
"code": "# @param {Integer} n\n# @param {Integer[][]} edges\n# @return {Integer[][]}\ndef get_ancestors(n, edges)\n \nend",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Swift",
|
|
"langSlug": "swift",
|
|
"code": "class Solution {\n func getAncestors(_ n: Int, _ edges: [[Int]]) -> [[Int]] {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Go",
|
|
"langSlug": "golang",
|
|
"code": "func getAncestors(n int, edges [][]int) [][]int {\n \n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Scala",
|
|
"langSlug": "scala",
|
|
"code": "object Solution {\n def getAncestors(n: Int, edges: Array[Array[Int]]): List[List[Int]] = {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Kotlin",
|
|
"langSlug": "kotlin",
|
|
"code": "class Solution {\n fun getAncestors(n: Int, edges: Array<IntArray>): List<List<Int>> {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Rust",
|
|
"langSlug": "rust",
|
|
"code": "impl Solution {\n pub fn get_ancestors(n: i32, edges: Vec<Vec<i32>>) -> Vec<Vec<i32>> {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "PHP",
|
|
"langSlug": "php",
|
|
"code": "class Solution {\n\n /**\n * @param Integer $n\n * @param Integer[][] $edges\n * @return Integer[][]\n */\n function getAncestors($n, $edges) {\n \n }\n}",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "TypeScript",
|
|
"langSlug": "typescript",
|
|
"code": "function getAncestors(n: number, edges: number[][]): number[][] {\n\n};",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Racket",
|
|
"langSlug": "racket",
|
|
"code": "(define/contract (get-ancestors n edges)\n (-> exact-integer? (listof (listof exact-integer?)) (listof (listof exact-integer?)))\n\n )",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Erlang",
|
|
"langSlug": "erlang",
|
|
"code": "-spec get_ancestors(N :: integer(), Edges :: [[integer()]]) -> [[integer()]].\nget_ancestors(N, Edges) ->\n .",
|
|
"__typename": "CodeSnippetNode"
|
|
},
|
|
{
|
|
"lang": "Elixir",
|
|
"langSlug": "elixir",
|
|
"code": "defmodule Solution do\n @spec get_ancestors(n :: integer, edges :: [[integer]]) :: [[integer]]\n def get_ancestors(n, edges) do\n\n end\nend",
|
|
"__typename": "CodeSnippetNode"
|
|
}
|
|
],
|
|
"stats": "{\"totalAccepted\": \"9.7K\", \"totalSubmission\": \"21K\", \"totalAcceptedRaw\": 9739, \"totalSubmissionRaw\": 21006, \"acRate\": \"46.4%\"}",
|
|
"hints": [
|
|
"Consider how reversing each edge of the graph can help us.",
|
|
"How can performing BFS/DFS on the reversed graph help us find the ancestors of every node?"
|
|
],
|
|
"solution": null,
|
|
"status": null,
|
|
"sampleTestCase": "8\n[[0,3],[0,4],[1,3],[2,4],[2,7],[3,5],[3,6],[3,7],[4,6]]",
|
|
"metaData": "{\n \"name\": \"getAncestors\",\n \"params\": [\n {\n \"name\": \"n\",\n \"type\": \"integer\"\n },\n {\n \"type\": \"integer[][]\",\n \"name\": \"edges\"\n }\n ],\n \"return\": {\n \"type\": \"list<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. Deleting an item in a hash:</b>\\r\\n<pre>\\r\\nvoid delete_user(struct hash_entry *user) {\\r\\n HASH_DEL(users, user); \\r\\n}\\r\\n</pre>\\r\\n</p>\"], \"csharp\": [\"C#\", \"<p><a href=\\\"https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/csharp-9\\\" target=\\\"_blank\\\">C# 10 with .NET 6 runtime</a></p>\\r\\n\\r\\n<p>Your code is compiled with debug flag enabled (<code>/debug</code>).</p>\"], \"javascript\": [\"JavaScript\", \"<p><code>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 ES6 features</a>.</p>\\r\\n\\r\\n<p><a href=\\\"https://lodash.com\\\" target=\\\"_blank\\\">lodash.js</a> library is included by default.</p>\\r\\n\\r\\n<p>For Priority Queue / Queue data structures, you may use <a href=\\\"https://github.com/datastructures-js/priority-queue\\\" target=\\\"_blank\\\">datastructures-js/priority-queue</a> and <a href=\\\"https://github.com/datastructures-js/queue\\\" target=\\\"_blank\\\">datastructures-js/queue</a>.</p>\"], \"ruby\": [\"Ruby\", \"<p><code>Ruby 3.1</code></p>\\r\\n\\r\\n<p>Some common data structure implementations are provided in the Algorithms module: https://www.rubydoc.info/github/kanwei/algorithms/Algorithms</p>\"], \"swift\": [\"Swift\", \"<p><code>Swift 5.5.2</code>.</p>\"], \"golang\": [\"Go\", \"<p><code>Go 1.17.6</code>.</p>\\r\\n\\r\\n<p>Support <a href=\\\"https://godoc.org/github.com/emirpasic/gods\\\" target=\\\"_blank\\\">https://godoc.org/github.com/emirpasic/gods</a> library.</p>\"], \"python3\": [\"Python3\", \"<p><code>Python 3.10</code>.</p>\\r\\n\\r\\n<p>Most libraries are already imported automatically for your convenience, such as <a href=\\\"https://docs.python.org/3/library/array.html\\\" target=\\\"_blank\\\">array</a>, <a href=\\\"https://docs.python.org/3/library/bisect.html\\\" target=\\\"_blank\\\">bisect</a>, <a href=\\\"https://docs.python.org/3/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>\"], \"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>\"], \"racket\": [\"Racket\", \"<p>Run with <code>Racket 8.3</code>.</p>\"], \"erlang\": [\"Erlang\", \"Erlang/OTP 24.2\"], \"elixir\": [\"Elixir\", \"Elixir 1.13.0 with Erlang/OTP 24.2\"]}",
|
|
"libraryUrl": null,
|
|
"adminUrl": null,
|
|
"challengeQuestion": null,
|
|
"__typename": "QuestionNode"
|
|
}
|
|
}
|
|
} |