Airbnb·Software Engineer·Technical Phone Screen·Intermediate

Intermediate

Jun 2026

Summary

Airbnb software engineer interview with a coding question around string formatting and ASCII table rendering. Pretty implementation-heavy, less algorithmic than I expected, but the edge case discussion is where things got interesting.

Questions Asked (1)

Given a list of sentences and a fixed column width, print each sentence as a row in a bordered ASCII table, with each row padded to the specified width and separated by horizontal dividers.

Algorithms & Data StructuresTechnical Trade-offs

Author's notes

The core implementation wasn't too bad once I started writing it out.

Create a free account to read the full note

AI HintsAI Generated

Suggested Approach

Start by clarifying requirements: input format, column width, border characters, and handling of sentences longer than the width. Then outline a modular solution: compute the maximum number of lines per sentence, build the top border, and for each sentence, print its wrapped lines with padding and a horizontal divider after each row. Discuss trade-offs between simple string concatenation and more efficient buffer building.

Pro tip: Mention that you would handle edge cases like empty sentences, sentences exactly equal to the width, and sentences that need wrapping, and that you would use a StringBuilder or equivalent for efficiency. Also, proactively discuss how you would test the solution with unit tests covering these cases.

1. Clarify Requirements and Constraints

Ask about the exact border characters (e.g., '+', '-', '|'), whether the width includes borders, how to handle sentences longer than the width (wrap or truncate), and if there are any constraints on input size.

2. Design the Algorithm

Break the problem into parts: compute the number of lines needed per sentence (ceil(length / width)), build the top border, and for each sentence, print its lines with left-aligned padding, followed by a horizontal divider.

3. Implement the Solution

Write code that iterates over sentences, splits them into chunks of the given width, pads each chunk to the width, and prints with borders. Use a StringBuilder for efficiency.

4. Analyze Complexity and Trade-offs

Discuss time complexity O(total characters) and space complexity O(width) for buffering. Compare approaches: building the entire output in memory vs. streaming line by line.

5. Test and Validate

Walk through test cases: empty list, single short sentence, sentence exactly width, sentence longer than width, multiple sentences. Verify output format matches expectations.

Key Points to Mention

Handling of sentences longer than the column width (wrapping vs. truncation) and how it affects row height.
Efficient string building using StringBuilder or equivalent to avoid O(n^2) concatenation.
Edge cases: empty input, empty strings, width of zero or negative, and sentences with special characters.
Modularity: separating border generation, padding, and wrapping logic for readability and testability.
Time and space complexity analysis, and potential optimizations for large inputs.
Testing strategy: unit tests for each edge case and visual verification of the table format.

AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.