Principal Member of Technical Staff

Oracle

You are given an m x n grid where each cell can have one of three values: 0 representing an empty cell, 1 representing a fresh orange, or 2 representing a rotten orange. Every minute, any fresh orange that is 4-directionally adjacent to a rotten orange becomes rotten. Return the minimum number of minutes that must elapse until no cell has a fresh orange. If it is impossible, return -1. For example, consider the following grid: [[2,1,1], [1,1,0], [0,1,1]] In this case, the function should return 4 because it takes 4 minutes for all the fresh oranges to rot. As another example, consider the following grid: [[2,1,1], [0,1,1], [1,0,1]] In this case, the function should return -1 because the orange in the bottom left will never rot. Here's how the rotting process would proceed in the first example: Initial state: [[2,1,1], [1,1,0], [0,1,1]] After 1 minute: [[2,2,1], [2,1,0], [0,1,1]] After 2 minutes: [[2,2,2], [2,2,0], [0,1,1]] After 3 minutes: [[2,2,2], [2,2,0], [0,2,1]] After 4 minutes: [[2,2,2], [2,2,0], [0,2,2]] All fresh oranges are now rotten after 4 minutes. Write a function to solve this problem efficiently. Consider edge cases such as an empty grid or a grid with no fresh oranges initially.

Oracle

Let's design a system for deleting all user data in a large-scale application. Consider the following requirements: Compliance: The system must adhere to data privacy regulations (e.g., GDPR, CCPA) regarding the right to be forgotten. This means all personal data must be permanently and irrevocably deleted. Data Scope: User data is distributed across various databases (e.g., relational, NoSQL), object storage, and potentially third-party services. Examples include: User profiles in a relational database (name, email, address). User-generated content (photos, videos) in object storage. User activity logs in a NoSQL database. User data cached in a Redis cluster. User accounts on integrated third-party services (e.g., payment processors, social media platforms). Performance: The deletion process should be efficient and not significantly impact the performance of other system operations. Consider the impact on databases and other services during peak hours. Consistency: The system must ensure data consistency. For example, if a user has dependencies on other data (e.g., a user is an administrator of a group), these dependencies must be handled correctly (e.g., reassigning ownership, deleting dependent data). Auditability: All deletion requests and actions must be logged for auditing and compliance purposes. The logs should record who requested the deletion, when it was requested, what data was deleted, and the outcome of the deletion process. Error Handling: The system should gracefully handle errors and retries. If a deletion fails in one component, it should be retried or rolled back appropriately, and alerts should be generated. Scalability: The system must be able to handle a large number of deletion requests concurrently. Data Minimization: Before initiating the deletion process, verify if data minimization techniques can be applied instead of complete deletion, such as anonymization or pseudonymization, especially for datasets needed for analytical purposes. Given these requirements, how would you design a system to handle user data deletion requests? Discuss the architecture, components, data flow, and any trade-offs you would consider.

Oracle

Okay, let's imagine we're at a career fair, and you have about two minutes to introduce yourself to a recruiter. Keeping that timeframe in mind, could you provide a concise overview of your background, skills, and career aspirations? Think of it as your elevator pitch. For example, you might highlight your key accomplishments from previous roles, discuss your proficiency in specific programming languages or technologies relevant to the target position, and briefly touch upon your career goals and what you're hoping to achieve in your next role. What makes you a great candidate?