CoursesTrees & GraphsGraph Foundations
Nodes, Edges, and the Visited Set
Graphs are just nodes plus edges — learn the adjacency list, the undirected two-way rule, and why cycles make a visited set mandatory.
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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