Radix Cache / Trie vs Radix Tree

CodingxAILast reported September 2025Low Frequency

Reported: 2× across candidate reports
First seen: July 2025
Last reported: September 2025
Reported outcome: mixed

Problem Overview

Design and implement a RadixCache — a prefix-compressed tree that stores sequences of integers (not characters). Support insert(sequence), which automatically merges shared prefixes into internal nodes and splits an existing node when a new sequence only partially overlaps its edge. The round is staged as three milestones. Milestone 1, basic…

2 candidate-reported follow-ups — the exact probes interviewers asked, with the trigger for each
The rest of the problem statement — full requirements, constraints, and edge cases
Approach and trade-offs — what passing candidates did, and the mistakes that sink people

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Verified Source

Every question is reconstructed from multiple independent candidate reports. Verbatim follow-ups, not invented ones.

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Interviewer Follow-ups

The exact follow-ups reported by candidates, with the trigger that prompts each one — plus the mistakes that sink people.