Algorithm Atlas

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Surrounded Regions: step-by-step visual explanation

Learn the Surrounded Regions problem with a step-by-step DSA animation. Follow the DFS (Connectivity) solution with synced C#, Python, and Java code.

DFS (Connectivity) pattern

Visited state prevents repeated work and lets the traversal distinguish new paths from edges returning to earlier nodes.

Difficulty: Medium · Approach: Visible frontier and visited order

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