File System Permissions Management

Description

Prompt

Implement file system permissions management. You need to handle three data structures: Teams, Folders, and Files.

• Each team, folder, and file has a list of user IDs indicating who can access it.
• If a user can access a higher-level team/folder/file, they can also access all nested subfolders/files.

APIs

• init(teams, folders, files): Initialize and store the structures.
• get_fewest(user_id): Return the fewest teams/folders/files that cover all resources the user can access (i.e., the highest-level nodes granting access).

Example

Team1
  /   
Folder1(A) Folder2
  /  \        |
file1(A) file2 Folder3(A)

For user A, return [Folder1, Folder3] as the minimal set of top-level nodes covering their access.

Constraints

• init() does not return data; it stores state.
• user_ids provided as lists; access checks should be efficient.
• Aim for memory- and performance-aware design; consider up to thousands of nodes.

Notes

• System design / data-structure design; phone screen level.