CoursesTrees & GraphsGrid Traversal
Boss: Rotting Oranges
The island's final test: every rotten orange spreads at once, so minutes are BFS LAYERS from ALL sources — not steps of one walker. Seed the whole queue at minute 0, count the fresh, and answer -1 only when a fresh orange is unreachable.
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.
Pro starts with a 3 day free trial. The app store decides who is eligible for an introductory offer, and a lapsed subscription does not get another one.
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