CoursesBacktracking & GreedyBacktracking Foundations
Permutations
Order matters: every unused element branches at every level, tracked by used[] flags — and every mark must be undone on the way back.
AlgoFox Pro
Backtracking & Greedy 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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