{ "data": { "question": { "questionId": "1000310", "questionFrontendId": "剑指 Offer II 113", "categoryTitle": "LCOF2", "boundTopicId": 910304, "title": "课程顺序", "titleSlug": "QA2IGt", "content": "

English description is not available for the problem. Please switch to Chinese.

\n", "translatedTitle": "课程顺序", "translatedContent": "

现在总共有 numCourses 门课需要选，记为 0 到 numCourses-1。

\n\n

给定一个数组 prerequisites ，它的每一个元素 prerequisites[i] 表示两门课程之间的先修顺序。 例如 prerequisites[i] = [ai, bi] 表示想要学习课程 ai ，需要先完成课程 bi 。

\n\n

请根据给出的总课程数  numCourses 和表示先修顺序的 prerequisites 得出一个可行的修课序列。

\n\n

可能会有多个正确的顺序，只要任意返回一种就可以了。如果不可能完成所有课程，返回一个空数组。

\n\n

 

\n\n

示例 1:

\n\n
\n输入: numCourses = 2, prerequisites = [[1,0]] \n输出: [0,1]\n解释: 总共有 2 门课程。要学习课程 1，你需要先完成课程 0。因此，正确的课程顺序为 [0,1] 。
\n\n

示例 2:

\n\n
\n输入: numCourses = 4, prerequisites = [[1,0],[2,0],[3,1],[3,2]]\n输出: [0,1,2,3] or [0,2,1,3]\n解释: 总共有 4 门课程。要学习课程 3，你应该先完成课程 1 和课程 2。并且课程 1 和课程 2 都应该排在课程 0 之后。\n 因此，一个正确的课程顺序是 [0,1,2,3] 。另一个正确的排序是 [0,2,1,3] 。\n
\n\n

示例 3:

\n\n
\n输入: numCourses = 1, prerequisites = [] \n输出: [0]\n解释: 总共 1 门课，直接修第一门课就可。
\n\n

 

\n\n

提示:

\n\n\n\n

 

\n\n

注意：本题与主站 210 题相同：https://leetcode-cn.com/problems/course-schedule-ii/

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