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CoursesTrees & GraphsTopological Sort

In-Degrees and Kahn's Peel

Dependency edges point from prerequisite to dependent — count unmet prerequisites as in-degree, peel the zeros, and a valid order falls out.

Complete codeMultiple choice6 exercises, 5 min
AlgoFox Pro

Trees & Graphs is part of AlgoFox Pro

You can read the whole course outline here. The exercises are in the app, along with your streak, your mistake review, and the progress that carries across your devices.

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