![Prereqs [[1,0],[2,0],[3,1],[3,2]] vs a 2-cycle [[1,0],[0,1]] overview diagram](/blogs/topological-sort-explained-valid-vs-cyclic-course-schedules/diagrams/hero.svg)
intermediate8 min · Oct 1, 2026
Topological Sort Explained: Valid vs Cyclic Course Schedules
Learn topological sort by tracing Kahn's algorithm on a valid 4-course dependency graph vs an impossible 2-cycle schedule.
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![2 closest of [[1,3],[-2,2],[2,-2]] overview diagram](/blogs/k-closest-points-to-origin-explained-1-3-2-2-2-2-walkthrough/diagrams/hero.svg)
