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Google·Software Engineer·Onsite - Coding / Algorithms·Intermediate

IntermediatePending
Jul 2026

Summary

Two Google SWE coding rounds, mixed results. First went pretty clean, second got messy toward the end with a debugging spiral and no time left to cover complexity. Now sitting here wondering if that's enough to skip a third round or if I'm about to get the 'additional interview' email.

Questions Asked (3)

Q1

Solve a coding problem and explain the time and space complexity of your solution.

Algorithms & Data StructuresTechnical Trade-offs
Author's notes

Finished this one with time to spare, walked through complexity, felt good.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem and constraints, then discuss a brute-force solution before optimizing. Implement the optimal solution with clean code, test with edge cases, and analyze time and space complexity. Explain trade-offs and potential improvements.

Pro tip: At Google, interviewers value clear communication and structured problem-solving over just getting the right answer. Think aloud, explain your reasoning, and proactively discuss alternative approaches and their trade-offs.

1. Understand and Clarify

Restate the problem in your own words, ask clarifying questions about input/output, constraints, and edge cases. Confirm assumptions with the interviewer.

2. Explore Approaches

Discuss a brute-force solution first, then propose optimized approaches. Compare their time and space complexities and explain why you choose a particular approach.

3. Implement and Test

Write clean, modular code with meaningful variable names. Walk through your code with a small example and test edge cases to ensure correctness.

4. Analyze Complexity

Clearly state the time and space complexity of your solution, explaining how you derived them. Discuss trade-offs between time and space if applicable.

5. Reflect and Optimize

Consider if further optimization is possible or if there are alternative solutions with better trade-offs. Discuss potential improvements and their implications.

Key Points to Mention

  • Clarify problem constraints and edge cases before coding.
  • Start with a brute-force solution and then optimize.
  • Explain the reasoning behind choosing a specific data structure or algorithm.
  • Analyze time and space complexity rigorously, including best, average, and worst cases.
  • Discuss trade-offs between different approaches (e.g., time vs. space).
  • Test code with edge cases and walk through examples.

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

Q2

Given a second coding problem in the same session, implement a solution under time pressure.

Algorithms & Data Structures
Author's notes

Knew the approach immediately, which I think saved me a little.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem and constraints to ensure you understand the requirements, then discuss a brute-force solution before optimizing. Implement the optimized solution cleanly, test with edge cases, and analyze time and space complexity.

Pro tip: Communicate your thought process continuously, even when stuck, and manage your time by setting checkpoints (e.g., 5 minutes for understanding, 15 for coding, 5 for testing). If you finish early, discuss potential optimizations or alternative approaches.

1. Understand and Clarify

Restate the problem in your own words, ask clarifying questions about input/output, constraints, and edge cases. Confirm your understanding with the interviewer before proceeding.

2. Discuss Approaches

Brainstorm multiple solutions, starting with a brute-force approach, then optimize. Verbally compare trade-offs in time and space complexity, and choose the best one with interviewer buy-in.

3. Implement Cleanly

Write code in a structured, modular way with meaningful variable names. Explain your logic as you code, and avoid getting bogged down in minor syntax details.

4. Test and Debug

Walk through your code with a small example, then test edge cases (empty input, large input, duplicates, etc.). If you find a bug, debug systematically and explain your fix.

5. Analyze and Optimize

State the time and space complexity of your solution. If time permits, suggest further optimizations or alternative approaches, and discuss any trade-offs.

Key Points to Mention

  • Clarify ambiguities and constraints before coding to avoid misunderstandings.
  • Start with a brute-force solution to establish a baseline, then optimize.
  • Communicate your thought process clearly and continuously.
  • Write clean, readable code with good naming and structure.
  • Test with edge cases and walk through examples to verify correctness.
  • Analyze time and space complexity and discuss potential improvements.

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

Q3

Implement a solution to a coding problem, optimizing data structure choices as you go.

Algorithms & Data StructuresTechnical Trade-offs
Author's notes

This is the one that hurt.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem requirements and constraints, then propose a brute-force solution before optimizing. Discuss data structure trade-offs (time vs. space) and justify your final choice based on the problem's expected input size and operations.

Pro tip: Verbalize your thought process as you code, and proactively test edge cases (empty input, large input, duplicates) to demonstrate thoroughness and debugging skills.

1. Clarify Requirements

Ask questions to understand input size, constraints, expected output, and any special cases. Confirm assumptions before proceeding.

2. Outline Brute-Force Approach

Describe a simple, correct solution and analyze its time and space complexity. This sets a baseline for optimization.

3. Optimize with Data Structures

Identify bottlenecks and propose better data structures (e.g., hash maps, heaps, trees) to improve efficiency. Discuss trade-offs.

4. Implement and Test

Write clean, modular code while explaining your logic. Test with normal and edge cases, and debug if necessary.

5. Review and Discuss Trade-offs

Summarize the final solution's complexity, mention alternative approaches, and reflect on potential improvements or real-world considerations.

Key Points to Mention

  • Time and space complexity analysis (Big O notation) for each approach
  • Trade-offs between different data structures (e.g., hash map vs. array vs. tree)
  • Edge cases and how to handle them (empty input, large input, duplicates, etc.)
  • Code readability and modularity (e.g., helper functions, meaningful variable names)
  • Testing strategy (unit tests, boundary cases, performance tests)
  • Scalability and real-world applicability of the chosen solution

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