Group employees by shared interests
Company: Palantir
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: Medium
Interview Round: Technical Screen
Given N employees, each with an integer id and a set of interests (strings), write an algorithm to find all employees who share at least one common interest. Return either
(a) a mapping from each interest to the sorted list of employee ids who have it, and/or
(b) the list of all unique employee-id pairs (u, v) that share one or more interests. Analyze time and space complexity and provide code in your preferred language.
Quick Answer: This question evaluates a candidate's competency in organizing and querying collections, mapping relationships between entities, and reasoning about algorithmic time and space complexity within data structures and grouping operations.