Course Schedule IV
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 ai first if you want to take course bi.
- For example, the pair
[0, 1]indicates that you have to take course0before you can take course1.
Prerequisites can also be indirect. If course a is a prerequisite of course b, and course b is a prerequisite of course c, then course a is a prerequisite of course c.
You are also given an array queries where queries[j] = [uj, vj]. For the j^th query, you should answer whether course uj is a prerequisite of course vj or not.
Return a boolean array answer, where answer[j] is the answer to the j^th query.
Example 1
Input
numCourses = 2, prerequisites = [[1,0]], queries = [[0,1],[1,0]]Output
[false,true]The pair [1, 0] indicates that course 1 must be taken before course 0, so course 0 is not a prerequisite of course 1, but course 1 is a prerequisite of course 0.
Example 2
Input
numCourses = 2, prerequisites = [], queries = [[1,0],[0,1]]Output
[false,false]There are no prerequisites, and each course is independent.
Constraints
- 2 <= numCourses <= 100
- 0 <= prerequisites.length <= (numCourses * (numCourses - 1) / 2)
- prerequisites[i].length == 2
- 0 <= ai, bi <= numCourses - 1
- ai != bi
- All the pairs [ai, bi] are unique.
- The prerequisites graph has no cycles.
- 1 <= queries.length <= 10^4
- 0 <= ui, vi <= numCourses - 1
- ui != vi