Package g0201_0300.s0207_course_schedule

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    207 - Course Schedule\.

    Medium

    There are a total of numCourses courses you have to take, labeled from 0 to numCourses - 1. You are given an array prerequisites where <code>prerequisitesi = a<sub>i</sub>, b<sub>i</sub></code> indicates that you must take course <code>b<sub>i</sub></code> first if you want to take course <code>a<sub>i</sub></code>.

    • For example, the pair [0, 1], indicates that to take course 0 you have to first take course 1.

    Return true if you can finish all courses. Otherwise, return false.

    Example 1:

    Input: numCourses = 2, prerequisites = \[\[1,0]]

    Output: true

    Explanation: There are a total of 2 courses to take. To take course 1 you should have finished course 0. So it is possible.

    Example 2:

    Input: numCourses = 2, prerequisites = \[\[1,0],0,1]

    Output: false

    Explanation: There are a total of 2 courses to take. To take course 1 you should have finished course 0, and to take course 0 you should also have finished course 1. So it is impossible.

    Constraints:

    • 1 &lt;= numCourses &lt;= 2000

    • 0 &lt;= prerequisites.length &lt;= 5000

    • prerequisites[i].length == 2

    • <code>0 <= a<sub>i</sub>, b<sub>i</sub>< numCourses</code>

    • All the pairs prerequisitesi are unique.

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Boolean canFinish(Integer numCourses, Array<IntArray> prerequisites)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait