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.
[0, 1] indicates that you have to take course 0 before you can take course 1.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 jth 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 jth query.
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Example 1:
\n![\"\"](\"https://assets.leetcode.com/uploads/2021/05/01/courses4-1-graph.jpg\")
\n\nInput: numCourses = 2, prerequisites = [[1,0]], queries = [[0,1],[1,0]]\nOutput: [false,true]\nExplanation: The pair [1, 0] indicates that you have to take course 1 before you can take course 0.\nCourse 0 is not a prerequisite of course 1, but the opposite is true.\n\n\n
Example 2:
\n\n\nInput: numCourses = 2, prerequisites = [], queries = [[1,0],[0,1]]\nOutput: [false,false]\nExplanation: There are no prerequisites, and each course is independent.\n\n\n
Example 3:
\n![\"\"](\"https://assets.leetcode.com/uploads/2021/05/01/courses4-3-graph.jpg\")
\n\nInput: numCourses = 3, prerequisites = [[1,2],[1,0],[2,0]], queries = [[1,0],[1,2]]\nOutput: [true,true]\n\n\n
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Constraints:
\n\n2 <= numCourses <= 1000 <= prerequisites.length <= (numCourses * (numCourses - 1) / 2)prerequisites[i].length == 20 <= ai, bi <= n - 1ai != bi[ai, bi] are unique.1 <= queries.length <= 1040 <= ui, vi <= n - 1ui != viCompiled with clang 11 using the latest C++ 20 standard.
Your code is compiled with level two optimization (-O2). AddressSanitizer is also enabled to help detect out-of-bounds and use-after-free bugs.
Most standard library headers are already included automatically for your convenience.
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