Staff Software Engineer - Systems Infrastructure

LinkedIn

Okay, here are the Data Structures and Algorithms (DSA) and Machine Learning (ML) questions: DSA Question: Implement a Circular Queue Description: Design and implement a circular queue data structure. A circular queue, also known as a ring buffer, is a queue that reuses space. When the rear of the queue reaches the end of the array, it wraps around to the beginning, provided there are empty slots. Requirements: Implement the CircularQueue class with the following methods: CircularQueue(int capacity): Initializes the queue with a specified capacity. enqueue(int value): Adds an element to the rear of the queue. Returns true if successful, false otherwise (if the queue is full). dequeue(): Removes an element from the front of the queue. Returns the removed element. Returns -1 if the queue is empty. front(): Returns the element at the front of the queue without removing it. Returns -1 if the queue is empty. rear(): Returns the element at the rear of the queue without removing it. Returns -1 if the queue is empty. isEmpty(): Returns true if the queue is empty, false otherwise. isFull(): Returns true if the queue is full, false otherwise. Example: CircularQueue q = new CircularQueue(5); q.enqueue(1); // returns true q.enqueue(2); // returns true q.enqueue(3); // returns true q.enqueue(4); // returns true q.enqueue(5); // returns true q.enqueue(6); // returns false (queue is full) q.dequeue(); // returns 1 q.enqueue(6); // returns true q.front(); // returns 2 q.rear(); // returns 6 ML Question: Explain Gradient Descent Description: Explain the concept of gradient descent in machine learning. Cover the following aspects: What is gradient descent and why is it used? Explain the basic steps involved in the gradient descent algorithm. Describe different types of gradient descent (e.g., Batch, Stochastic, Mini-batch). What are the challenges associated with gradient descent (e.g., local minima, learning rate selection)? How can these challenges be addressed? Example Scenario: Suppose you are training a linear regression model. The cost function is Mean Squared Error (MSE). Explain how gradient descent would be used to find the optimal values for the model's coefficients (slope and intercept) that minimize the MSE.

LinkedIn

Let's design the LinkedIn feed. Consider the user experience, key features, scalability, and personalization aspects. For instance, how would you prioritize content from connections versus suggested content? How would you handle different content types like text, images, videos, and articles? How do you design a system to ensure that the feed remains responsive even with millions of active users? How would you personalize the feed to show users content they are most likely interested in, and what data would you use to achieve this personalization? Finally, how would you prevent the spread of misinformation or harmful content within the feed?

LinkedIn

Let's walk through a past project you've worked on. I'm interested in understanding your approach, the challenges you faced, and how you overcame them. To start, please describe a project where you had significant ownership and responsibility. Elaborate on the project's goals, your specific role, and the technologies you utilized. For example, perhaps you led the development of a new feature for a mobile application using React Native, or you were responsible for optimizing a database query that was causing performance bottlenecks. As you describe the project, please highlight the key decisions you made and the rationale behind them. I'd also like to hear about any unexpected obstacles you encountered and the steps you took to address them. This could include technical challenges, team coordination issues, or changes in project requirements. For instance, how did you handle a situation where a critical dependency was deprecated, or when a team member was unable to complete their assigned tasks? Finally, I'm keen to learn about the outcomes of the project and how you measured its success. What were the key performance indicators (KPIs) that you tracked, and what were the results? Did you achieve the project's goals, and what lessons did you learn from the experience? Please provide specific examples and quantify the impact of your contributions whenever possible. This walkthrough will help me understand your problem-solving skills, technical expertise, and ability to work effectively in a team environment.