Design a streaming median structure
Company: Amazon
Role: Software Engineer
Category: Coding & Algorithms
Difficulty: Medium
Interview Round: Onsite
Design a data structure for a number stream that supports: add(num: int) in O(log n) time and median() -> float in O(
1) or O(log n) time. It must handle up to 10^6 operations, duplicates, and both even/odd counts. Describe the APIs, internal invariants, and prove the time/space complexity. Implement the core methods.
Quick Answer: This question evaluates a candidate's competency in designing efficient data structures and algorithmic reasoning for dynamic order-statistics and streaming data within the Coding & Algorithms domain, emphasizing APIs, internal invariants, and rigorous time/space complexity analysis.
