← Perplexity Interview Insights
Go with a trie from the start, don't second-guess it.
Start by clarifying requirements and defining the core operations (create, list, read, write). Then design a tree-based data structure with nodes representing files and directories, and implement the operations using appropriate data structures like hash maps for children and strings for content. Discuss trade-offs and potential optimizations.
Pro tip: Mention that you would use a trie-like structure with hash maps for efficient lookups, and discuss how to handle edge cases like path normalization and concurrent access. This shows attention to detail and scalability.
Ask about expected operations, path formats (absolute vs relative), file/directory naming rules, and whether concurrency or persistence is needed. This ensures you build the right abstraction.
Propose a tree where each node is either a file or directory. Use a hash map to store children (name -> node) for O(1) lookups, and store file content as a string or byte array.
Outline methods for create (file/dir), list (return children names), read (return content), and write (update content). Handle path resolution by splitting on '/' and traversing the tree.
Discuss errors like creating existing files, accessing non-existent paths, and invalid operations (e.g., writing to a directory). Also consider path normalization (e.g., '..', '.').
Talk about potential improvements: caching, concurrency (locks), memory efficiency, and supporting additional operations like delete or move. Mention trade-offs between simplicity and performance.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.