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Google·Software Engineer·Technical Phone Screen·Junior

JuniorPending
Sep 2026

Summary

Two-round Google SWE intern coding interviews, both on the easier side technically but with enough follow-up pressure to make things interesting. First round went pretty clean until the code review phase, second round had a logic bug caught by a test case the interviewer threw at me. First interview overall.

Questions Asked (2)

Q1

Solve a straightforward algorithmic problem, then justify your choice of approach and walk through edge cases.

Algorithms & Data StructuresTechnical Trade-offs
Author's notes

Picked a recursive solution because it was the cleanest to write.

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AI HintsAI Generated

Suggested Approach

Start by restating the problem and clarifying constraints, then propose a simple brute-force solution before optimizing. Implement the optimal solution while explaining your reasoning, and finally walk through edge cases and test your code with examples.

Pro tip: Verbalize your thought process continuously, as Google evaluates problem-solving and communication equally. Before coding, explicitly state the time and space complexity of your approach and compare it to alternatives.

1. Understand and Clarify

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

2. Explore Approaches

Discuss a brute-force solution and its complexity, then propose an optimized approach. Explain the trade-offs between different algorithms or data structures.

3. Implement and Explain

Write clean, modular code while explaining each step. Use meaningful variable names and handle edge cases as you go.

4. Test and Validate

Walk through your code with a few test cases, including edge cases like empty input, single element, duplicates, or large values. Verify correctness and complexity.

5. Reflect and Optimize

If time permits, discuss potential improvements or alternative solutions. Summarize why your chosen approach is optimal for the given constraints.

Key Points to Mention

  • Time and space complexity analysis of each approach
  • Trade-offs between different data structures (e.g., hash map vs. sorting)
  • Edge cases: empty input, single element, duplicates, negative numbers, overflow
  • Modularity and readability of code
  • Testing methodology: unit tests, boundary cases, and stress testing
  • Communication: explaining thought process and justifying decisions

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

Q2

Given a non-standard algorithmic problem, discuss the memory vs. time complexity tradeoffs between two different implementation approaches.

Algorithms & Data StructuresTechnical Trade-offs
Author's notes

Interviewer pushed back on my approach and suggested something more memory-efficient.

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AI HintsAI Generated

Suggested Approach

Start by clarifying the problem constraints and assumptions, then outline two distinct implementation approaches. Compare their time and space complexities, and discuss scenarios where each is preferable, emphasizing trade-offs and practical considerations.

Pro tip: Demonstrate awareness of real-world constraints like cache performance, memory hierarchy, and scalability; mention that asymptotic analysis alone may not capture practical performance differences.

1. Clarify the Problem

Ask clarifying questions to understand input size, constraints, expected operations, and any special conditions. This ensures you address the correct problem and sets the stage for meaningful trade-off analysis.

2. Propose Two Approaches

Briefly describe two viable algorithms or data structures to solve the problem, highlighting their core mechanisms (e.g., hash map vs. sorting, iterative vs. recursive).

3. Analyze Complexities

For each approach, derive the time and space complexity in big-O notation, considering best, average, and worst cases. Be precise about auxiliary space versus total space.

4. Discuss Trade-offs

Compare the approaches: when would you choose one over the other? Consider factors like input size, memory limits, time constraints, and typical usage patterns.

5. Conclude with Recommendation

Summarize which approach is generally preferable and under what conditions, showing balanced judgment and practical insight.

Key Points to Mention

  • Big-O time and space complexity for each approach
  • Auxiliary space vs. total space usage
  • Impact of input size and distribution on performance
  • Real-world constraints: memory limits, cache effects, parallelism
  • Scalability and maintainability of each solution
  • Potential optimizations or hybrid approaches

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