Research Scientist L5, Algorithms Engineering

Netflix

Write a function that validates if a given string is a valid representation of an integer. The function should handle positive, negative, and zero values. It should also account for leading/trailing spaces, but return false if there are any non-numeric characters other than a single leading '+' or '-' sign. Details: The input is a string. The output is a boolean: true if the string represents a valid integer, false otherwise. A valid integer string can start with an optional '+' or '-' sign. The rest of the string must contain only digits. Leading and trailing whitespace should be ignored. The string must not contain any other non-numeric characters. Examples: +123 should return true -456 should return true 0 should return true +007 should return true abc should return false 12.3 should return false 1a should return false should return false ++12 should return false --12 should return false 12+ should return false 12- should return false Considerations: Handle empty strings gracefully. Be mindful of potential integer overflow issues (although the function does not need to explicitly check for it). Focus on validating the format of the string. Ensure your solution efficiently handles various edge cases and invalid inputs. Your function should demonstrate clear, concise, and well-documented code.

Netflix

Let's delve into the Observer pattern. Imagine you're building a stock market application. You have a central Stock object that holds the current price. Multiple components, such as a PriceDisplay, a Graph, and an AlertSystem, need to update whenever the Stock price changes. Explain the Observer pattern: Describe the core components (Subject, Observer) and how they interact. Explain the benefits of using this pattern in scenarios like the stock market application. Design Implementation: Provide a simplified code implementation of the Observer pattern for this stock market scenario. Show how the Stock object (Subject) would manage its observers (PriceDisplay, Graph, AlertSystem) and how these observers would receive updates when the stock price changes. Focus on clarity and demonstrating the core concepts. Trade-offs: What are the potential drawbacks of using the Observer pattern, especially in a system with a large number of observers? How might you mitigate these issues (e.g., using weak references, asynchronous updates)? Alternatives: Are there alternative patterns or approaches you might consider instead of the Observer pattern for this type of scenario? What are the pros and cons of these alternatives compared to the Observer pattern? Real-world Examples: Besides a stock market application, can you describe other real-world examples where the Observer pattern is commonly used?

Netflix

Describe a time when you had a deadline you couldn't meet. What did you do, and what was the outcome? For example, imagine you were tasked with developing a new feature for a popular mobile app with a launch date tied to a major industry event. Due to unforeseen technical complexities or resource constraints, it became clear that you wouldn't be able to deliver the complete feature set by the deadline. How did you communicate this to your team and stakeholders? What steps did you take to mitigate the impact of the missed deadline? Did you try to renegotiate the scope or timeline? How did you prioritize the remaining tasks, and what alternative solutions did you explore to deliver value within the limited timeframe? What did you learn from this experience, and how did it influence your approach to project management and deadline setting in subsequent projects?