Senior Data Engineer, Finance Data and Analytics

Google

Given n pairs of parentheses, what is the total number of different, valid combinations of those parenthesis? For example: For n = 1, the only valid combination is (), so the answer is 1. For n = 2, the valid combinations are ()() and (()), so the answer is 2. For n = 3, the valid combinations are ((())), (()()), (())(), ()(()), and ()()(), so the answer is 5. Calculate the number of valid parenthesis combinations for a given n. Explain the formula or method used to arrive at the answer. What is the underlying mathematical concept at play here, and how does it ensure that we only count valid combinations, avoiding invalid ones such as )()(? Detail the relationship between this problem and Catalan numbers, and discuss how this relationship can be utilized to efficiently compute the number of valid combinations, even for relatively large values of n.

Google

Let's design a system for URL shortening, like TinyURL. Assume that we need to handle a large number of requests, say billions of URLs per day. Consider the following: Functional Requirements: The system should generate a shorter, unique alias for a given URL. Users should be able to enter a shortened URL and be redirected to the original URL. The shortened URLs should be relatively short. Non-Functional Requirements: The system should be highly available. URL redirection should be as fast as possible. The shortened URLs should be unique. The system should be scalable to handle a large number of URLs and requests. Considerations: How would you design the data model to store the mappings between shortened and original URLs? What algorithms would you use to generate the shortened URLs? Consider the trade-offs between different algorithms. How would you handle collisions (when the same shortened URL is generated for two different original URLs)? What kind of database would you use and why? How would you handle the high volume of traffic and ensure low latency for redirection? Consider caching strategies. How would you scale the system to handle future growth? Walk me through your design, explaining your choices and the rationale behind them. Include diagrams and specific technologies where appropriate. Explain how you would ensure the system meets the requirements for availability, performance, and scalability.

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.