Software Engineer, Systems ML - Frameworks / Compilers / Kernels

Meta

You are given a binary tree. Write a function to flatten the binary tree into a linked list in-place. The linked list should be in the same order as a pre-order traversal of the binary tree. This means that for each node, the right pointer should point to the next node in the pre-order traversal, and the left pointer should be null. For example, consider the following binary tree: 1 / 2 5 / 3 4 6 After flattening, the tree should look like this: 1 -> 2 -> 3 -> 4 -> 5 -> 6 Each node's right pointer points to the next node in the pre-order traversal, and all left pointers are null. Clarifications: The function should modify the tree in-place. The pre-order traversal should be followed. The left pointers of all nodes should be set to null after flattening. Could you provide an efficient algorithm to accomplish this, and what is the time and space complexity of your solution?

Meta

Let's design a stories feature, similar to Instagram or WhatsApp. These stories should disappear after a friend views them and only be available for 24 hours after publishing. Consider the following aspects: Functionality: How would users create and upload stories (photos and videos)? How would users view stories from their friends? How would you implement the 24-hour expiration? How would you handle the disappearing aspect after viewing? Scalability: How would you handle a large number of users uploading and viewing stories simultaneously? How would you efficiently store and retrieve stories? How would you manage the storage as stories expire? Data Model: What database schema would you use to store story information (user, timestamp, media URL, view status)? How would you track which users have viewed a story? Technical Challenges: What are the potential challenges in implementing this feature? How would you address issues like latency, storage limitations, and data consistency? Edge Cases: How would you handle users with slow internet connections? What happens if a user uploads a story right before the 24-hour mark? How would you handle deleted user accounts and their associated stories?

Meta

Tell me about your best project. To provide a comprehensive overview, please address the following points: Project Overview: What was the project's purpose and goals? What problem did it solve or what opportunity did it address? Who was the target audience or end-user? Your Role and Responsibilities: Describe your specific role within the project team. What were your key responsibilities and contributions? Did you lead any specific aspects of the project? If so, elaborate. Technical Details: What technologies, languages, and frameworks did you use? Describe the architecture and design of the system. Were there any interesting or challenging technical aspects? Challenges and Solutions: What were the major challenges you faced during the project? How did you overcome these challenges? Be specific about the solutions you implemented. Did you have to make any trade-offs or compromises? Explain why. Outcomes and Impact: What were the measurable outcomes of the project? How did the project impact the organization or its users? Did the project achieve its intended goals? Lessons Learned: What did you learn from this project? What would you do differently if you were to undertake a similar project again? How has this project influenced your approach to software development? For example, if you developed an e-commerce platform, you might discuss how you implemented a scalable microservices architecture to handle high traffic, or how you used machine learning to personalize product recommendations. Be prepared to discuss technical details, challenges you faced, and the impact your project had on the users or the business. Focus on projects where you played a significant role and can demonstrate your technical skills and problem-solving abilities.