Implement a BST from Scratch in C++ (insert/search/delete)

Phone ScreenCitadelLast reported January 2026Low Frequency
Reported
1× across candidate reports
First seen
January 2026
Last reported
January 2026
Reported outcome
unknown

Problem Overview

Implement a binary search tree class from scratch with three operations: insert, search and delete. The round was in C++; this page uses Python. After the code, the interviewer asked: - What is the time complexity? - What happens in the worst case? - How would you make it balanced?…

  • 4 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.
Codex Fact-Checked
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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.
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