Firmware Engineer, Battery and Charging, Google Pixel

Google

Let's simulate a coding interview scenario. I'd like you to solve a problem and articulate your thought process as you go. Imagine you're given an array of integers. Your task is to write a function that finds the length of the longest strictly increasing subsequence in that array. A strictly increasing subsequence is a sequence of numbers from the array such that each number is greater than the previous one, and their original order in the array is maintained. For example, in the array [1, 3, 2, 4, 5], one possible increasing subsequence is [1, 2, 4, 5], and the longest increasing subsequence is [1, 2, 4, 5], which has a length of 4. Another possible increasing subsequence is [1, 3, 4, 5] which has length of 4. Your function should return 4 in this case. Another example is [10, 9, 2, 5, 3, 7, 101, 18]. The longest increasing subsequence is [2, 3, 7, 18], which has a length of 4. Your function should return 4. Can you describe your approach and then implement the function? Consider edge cases, like an empty array or an array with only one element. How would your approach handle those? What is the time and space complexity of your solution?

Google

Let's design a simplified distributed key-value store. Assume we need to handle a high volume of read and write requests. The key-value store should support the following operations: get(key): Retrieves the value associated with the given key. put(key, value): Stores the value associated with the given key. Here are some specific considerations for the design: Scalability: The system should be able to scale horizontally to handle increasing amounts of data and traffic. Consider how data will be distributed across multiple servers. Consistency: Discuss the consistency model you would implement. Would you choose strong consistency or eventual consistency? What are the trade-offs? Provide a rationale for your choice. Elaborate on how your design ensures that reads return the most up-to-date data (or how it handles potential inconsistencies, if any). Fault Tolerance: How would the system handle server failures? Describe the mechanisms you would implement to ensure data durability and availability in the face of node failures. Explain the role of replication and how it impacts consistency. Data Partitioning: Describe your data partitioning strategy. Consider using techniques like consistent hashing or range-based partitioning. Explain how your chosen strategy affects load balancing and data locality. Provide a concrete example of how keys would be mapped to specific servers in your design. Caching: Where would you incorporate caching in your system to improve read performance? Discuss different caching strategies (e.g., client-side caching, server-side caching) and their implications. Walk me through the architectural components of your key-value store, including the roles of different servers, the communication protocols used, and the data flow for get and put operations. Explain any potential bottlenecks and how you would address them. For example, if consistent hashing is used, how do you handle nodes being added or removed from the cluster?

Google

Tell me about a time you had to sign a non-disclosure agreement (NDA). What were the key terms, and how did you ensure compliance while working on the project? Consider these points in your answer: Context: Briefly describe the project and the purpose of the NDA. Who were the parties involved, and what information was being protected? Key Terms: What were the most important clauses or restrictions outlined in the NDA? This could include limitations on sharing information, reverse engineering, or using the protected information for purposes outside the scope of the agreement. Compliance Measures: What specific steps did you take to ensure you and your team complied with the NDA? Did you implement any specific procedures, such as data encryption, access controls, or regular training? Challenges: Did you face any challenges in adhering to the NDA? If so, how did you overcome them? Did you need to seek clarification on any terms or consult with legal counsel? Outcome: What was the result of the project, and how did the NDA contribute to its success? Did the NDA effectively protect the confidential information, and were there any lessons learned from the experience? For example, perhaps you worked on a project involving a new algorithm for a company. The NDA might have restricted you from sharing the algorithm with anyone outside the project team, reverse engineering it, or using it for any other projects. You might have implemented access controls to limit who could access the algorithm's source code and conducted regular training sessions to remind the team of their obligations under the NDA. You should talk about how you proactively avoided violations and made sure your actions were fully within the legal scope of the agreement.