Course Schedule
There are a total of numCourses courses you have to take, labeled from 0 to numCourses - 1. You are given an array prerequisites where prerequisites[i] = [ai, bi] indicates that you must take course bi first if you want to take course ai.
- For example, the pair
[0, 1]indicates that to take course0you have to first take course1.
Return true if you can finish all courses. Otherwise, return false.
Example 1
Input
numCourses = 2, prerequisites = [[1,0]]Output
trueThere 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
falseThere are a total of 2 courses to take, but course 1 requires course 0 and course 0 requires course 1, so it is impossible.
Constraints
- 1 <= numCourses <= 2000
- 0 <= prerequisites.length <= 5000
- prerequisites[i].length == 2
- 0 <= ai, bi < numCourses
- All the pairs prerequisites[i] are unique.