Recognized it from a forum almost immediately, which helped a lot.
Start by clarifying requirements and scope with the interviewer, then design a hierarchical file system using a tree data structure with nodes representing files and directories. Implement core operations like create, read, write, delete, and list, and discuss trade-offs for scalability, persistence, and concurrency.
Pro tip: Demonstrate maturity by proactively discussing edge cases (e.g., permissions, symbolic links, concurrent access) and how you would test and iterate on the design, rather than jumping straight to code.
Ask questions to understand scope: in-memory vs. persistent, single-user vs. multi-user, expected operations, and performance constraints. This ensures you design the right system.
Propose a tree structure with nodes for files and directories, including metadata like name, size, timestamps, and permissions. Consider using a map for children to enable fast lookup.
Outline algorithms for create, read, write, delete, move, and list, specifying time and space complexity. Discuss how to handle path resolution and directory traversal.
Discuss how to scale (e.g., sharding, caching) and persist data (e.g., serialization, database). Mention trade-offs between in-memory and disk-based storage.
Cover permissions, symbolic links, concurrent access (locking), and error handling. Explain how you would test the implementation.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.