Identify Overlapping Sessions and Optimize Coverage
RobinhoodData Scientist · Technical Screen
Last updated
This interview question evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer for Identify Overlapping Sessions and Optimize Coverage states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Scenario
During the technical screen, candidates must implement interval algorithms used in fraud-detection pipelines to reconcile overlapping user activity windows.
Question
Given a list of login sessions for a single user, each as [start_time, end_time], determine if any sessions overlap. 2. If overlaps exist, return the minimal set of session IDs to remove so that the remaining sessions are non-overlapping while maximizing total covered time.
Hints
Sort intervals, track previous end; greedy removal similar to ‘Non-overlapping Intervals’.
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