Design user communication functions

Q: Design user communication functions

This question evaluates a candidate's understanding of in-memory data structures, undirected relationship modeling, and API design for managing mutable user communication links.

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Question

In-Memory Communication Manager

Context

Build a simple in-memory component that tracks which users can communicate with each other. Treat a communication link between two users as an undirected connection (if A can talk to B, then B can talk to A). Assume user IDs are hashable (e.g., strings or integers) and that the system runs in a single process.

Requirements

Implement the following functions:

connect(user_a, user_b): Create a bidirectional connection so the two users can communicate.
disconnect(user_a, user_b): Remove an existing bidirectional connection, if present.
clear(): Remove all existing user communications.

Also:

Describe the data structures you use.
Provide code for the above API.
Analyze the time and space complexity.

Assumptions

Connections are undirected and idempotent (calling connect twice for the same pair should not create duplicates or errors).
Self-connections (a user connected to itself) should be rejected or ignored.
Disconnecting a non-existent connection should be a no-op.
Creating a connection for users not yet seen should implicitly add them to the system.

Design user communication functions

In-Memory Communication Manager

Context

Requirements

Assumptions

Solution

Comments (0)

Design user communication functions

Overview

In-Memory Communication Manager

Context

Requirements

Assumptions

Solution

Comments (0)