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🔥Course Schedule: Topological Cycle DetectorMedium
DAILY PROBLEM OF THE DAY+50 XP • Daily Streak

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MediumTrees & Graphs•Acceptance: 47.2%

Course Schedule: Topological Cycle Detector

Targeted in FAANG & Tech OA:GoogleAmazonUber
Real-World Engineering Context
Fundamental to package dependency resolvers (npm, cargo, pip), Terraform execution DAGs, and build systems like Bazel.
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`. Return `true` if you can finish all courses. Otherwise, return `false`.

Sample Test Cases

Input: [2,[[1,0]]]
Expected: true
Input: [2,[[1,0],[0,1]]]
Expected: false
Input: [3,[[0,1],[0,2],[1,2]]]
Expected: true

Constraints

  • 1 <= numCourses <= 2000
  • 0 <= prerequisites.length <= 5000
  • prerequisites[i].length == 2
  • 0 <= ai, bi < numCourses
  • All the pairs prerequisites[i] are unique.
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