Staff Data Scientist, Research, Applied Research

Google

Given an unsorted array of integers, write a function to sort the array in ascending order using the merge sort algorithm. Explanation of Merge Sort:** Briefly explain the merge sort algorithm, highlighting its divide-and-conquer approach. Implementation:** Provide a step-by-step implementation of the merge sort algorithm. This includes: A mergeSort function that recursively divides the array into smaller subarrays. A merge function that merges two sorted subarrays into a single sorted array. Example:** Input array: [38, 27, 43, 3, 9, 82, 10] Expected output: [3, 9, 10, 27, 38, 43, 82] Efficiency:** Discuss the time and space complexity of merge sort. Why is merge sort considered an efficient sorting algorithm? How does it compare to other sorting algorithms like bubble sort or quicksort in terms of performance (best, average, and worst-case scenarios)? Constraints:** You are not allowed to use built-in sorting functions. The array can contain positive and negative integers. The solution must be implemented in a language of your choice (e.g., Python, Java, C++). Follow-up:** How would you modify the merge sort algorithm to sort the array in descending order? Could you implement an iterative version of merge sort instead of the recursive one? What are the trade-offs?

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 the most challenging project you have ever handled. To provide more context, please consider the following aspects in your response: Describe the project briefly: What were the project's goals, and what was your role? What made it challenging? Was it a technical hurdle, a difficult deadline, a complex team dynamic, ambiguous requirements, or something else? Provide specific examples of the challenges you faced. How did you overcome these challenges? What steps did you take to address the issues? What resources did you utilize? Did you have to learn new skills or technologies on the fly? What was the outcome? Were you able to successfully complete the project? If not, what were the lessons learned? What would you do differently next time? What was your biggest takeaway from the project? How did this experience shape your approach to future projects? Did it change your perspective on teamwork, problem-solving, or project management? For instance, perhaps you led a project to migrate a legacy system to a new cloud-based platform, and you encountered unexpected compatibility issues that required you to develop innovative workarounds. Or maybe you were part of a team that was tasked with developing a new feature for a popular product, but the requirements changed frequently, and the timeline was extremely tight. Sharing these types of details will help me understand the scope and complexity of the project and how you responded to the challenges involved.