Research Scientist, Machine Learning (PhD)

Meta

Write code to parse regular expressions including * (0 or more characters), + (1 or more characters), and . (1 exact character). For example: parse(a., ab) should return true. parse(a*, aaa) should return true. parse(a+, a) should return true. parse(a+, ) should return false. parse(a.*b, axyzb) should return true. parse(a.*b, axyz) should return false. parse(abc, abc) should return true. parse(abc, abd) should return false. Your function should take two strings as input: the regular expression and the string to match against. It should return a boolean indicating whether the string matches the regular expression. Focus on handling the special characters ., *, and +. Assume that other characters in the regular expression must match literally. Explain your approach and provide a clear, well-documented code implementation. Consider edge cases such as empty strings and null inputs. Also think about the time and space complexity of your solution, and try to optimize it for performance. Can you provide a solution using dynamic programming?

Meta

Design an Autocomplete Service Let's design an autocomplete service, similar to what you'd find in Google Search or a code editor. The service should provide suggestions as the user types a query. Consider the following requirements: Functionality: The service should return the top k most relevant suggestions based on the user's input. Suggestions should be ranked by popularity (e.g., frequency of search). The system should support a large number of concurrent users. The system should be able to handle a large vocabulary of terms. The service needs to provide real-time or near real-time suggestions (low latency). The service should be fault-tolerant and highly available. Example: If a user types softw, the service might return: [software engineer, software developer, software company, software jobs]. If a user types ja, the service might return: [java, javascript, jakarta, james]. Considerations: How would you store the data to enable fast lookups? How would you handle updates to the suggestion data (e.g., new terms, updated popularity)? How would you scale the system to handle a large number of requests? What algorithms and data structures would you use? How would you optimize for latency? How would you handle different languages or character sets? How would you measure the performance of the service? Walk me through the design of this autocomplete service, considering the key components, data structures, algorithms, and scaling strategies. Describe any trade-offs you would make.

Meta

Describe a time you had to work in an ambiguous environment. What was the situation, what actions did you take, and what was the result? Be specific and provide details about the ambiguity you faced. For example: Lack of Clear Requirements: Describe a project where the initial requirements were poorly defined or constantly changing. How did you navigate the uncertainty and ensure the project moved forward? Conflicting Information: Share an experience where you received conflicting information from different stakeholders. How did you reconcile these discrepancies and make informed decisions? Unclear Goals: Tell me about a time when the overall goals of a project or task were not well-defined. How did you work to clarify the objectives and achieve a successful outcome? Limited Resources: Describe a situation where you had to work with limited resources (time, budget, personnel). How did you prioritize your efforts and make the most of what you had available? New Technology or Domain: Share an experience where you had to work with a new technology or in a domain where you had limited prior experience. How did you quickly learn and adapt to the unfamiliar environment?