UI Engineer (L5) - Content Engineering

Netflix

Design and implement an LRU (Least Recently Used) cache. Your cache should support the following operations: get(key) - Gets the value (will always be positive) of the key if the key exists in the cache, otherwise returns -1. put(key, value) - Sets or inserts the value if the key is not already present. When the cache reaches its capacity, it should invalidate the least recently used item before inserting a new item. For the purpose of this question, when a new key is inserted, regard it as most recently used. The cache is initialized with a positive capacity. Example: LRUCache cache = new LRUCache(2); // capacity is 2 cache.put(1, 1); cache.put(2, 2); cache.get(1); // returns 1 cache.put(3, 3); // evicts key 2 cache.get(2); // returns -1 (not found) cache.put(4, 4); // evicts key 1 cache.get(1); // returns -1 (not found) cache.get(3); // returns 3 cache.get(4); // returns 4 Follow up: Could you do both operations in O(1) time complexity?

Netflix

Design a thread synchronization function to access common resources. Imagine you have multiple threads that need to access and modify a shared data structure, such as a counter or a list. Without proper synchronization, race conditions can occur, leading to unpredictable and incorrect results. For example, two threads might try to increment the same counter simultaneously, resulting in only one increment instead of two. Your task is to design a function or mechanism that allows these threads to safely access and modify the shared resource. Consider the following requirements: Mutual Exclusion: Only one thread should be able to access the shared resource at any given time. Fairness: Threads should not be indefinitely blocked from accessing the resource (no starvation). Efficiency: The synchronization mechanism should not introduce excessive overhead that significantly impacts performance. Explain your design choices, including the type of synchronization primitive you would use (e.g., mutex, semaphore, condition variable), how it would be implemented, and how it would ensure mutual exclusion, fairness, and efficiency. Provide code snippets or pseudocode to illustrate your solution. Discuss potential issues such as deadlocks and how to prevent them. How would your design handle a scenario with a high number of threads contending for the resource?

Netflix

Tell me about a time you faced a significant ethical dilemma. What made it difficult, and what was the outcome? Describe the situation in detail, explaining the context and the stakeholders involved. Explain your thought process as you evaluated the ethical considerations. What alternatives did you consider, and why did you choose the path you did? What was the result of your actions, and what did you learn from the experience? For example, perhaps you discovered a colleague was misrepresenting their work or claiming credit for someone else's contributions. Or maybe you identified a potential safety issue with a product or service that your company was preparing to launch. Discuss how you navigated the situation, ensuring that your actions aligned with your personal and professional values, while also considering the potential impact on your team, the company, and other stakeholders. Explain how you communicated your concerns and the steps you took to reach a resolution, reflecting on whether you would approach the situation differently in the future.