Senior Software Engineer - UberEats

Uber

You are given the head of a singly linked list. Implement a function to determine if the linked list is a palindrome. A palindrome is a sequence that reads the same backward as forward. Example 1: Input:** head = [1, 2, 2, 1] Output:** true Example 2: Input:** head = [1, 2, 3, 2, 1] Output:** true Example 3: Input:** head = [1, 2] Output:** false Constraints: The number of nodes in the list is in the range [1, 10^5]. 0 <= Node.val <= 9 Your function should efficiently determine if the linked list forms a palindrome. Consider space and time complexity optimizations. For instance, think about how you can achieve this without using extra space (O(1) space complexity) or minimizing the time complexity to O(n). Can you solve this by reversing the second half of the list and comparing it with the first half?

Uber

Let's design a room reservation system. Consider the following requirements: Users: The system should allow users to search for available rooms and make reservations. Rooms: Each room has a capacity, a list of available equipment (e.g., projector, whiteboard), and a location. Reservations: Reservations have a start time, an end time, a room, and a user. Conflicts: The system must prevent double-booking of rooms. If someone tries to book a room that is already booked during that timeframe, they should receive an error message. Searching: Users should be able to search for rooms based on criteria such as capacity, available equipment, location, and time slot. Admin: Admins should be able to add new rooms, modify room details, and view all reservations. Consider the data models, APIs, and system architecture. Provide a high-level overview of your design, including the key components and their interactions. What data structures would you use to efficiently store and retrieve room and reservation information? How would you handle concurrency and prevent race conditions when multiple users try to book the same room simultaneously? What are the trade-offs between different architectural choices (e.g., monolithic vs. microservices)? What API endpoints would you expose for common operations like searching for rooms, creating reservations, and canceling reservations? How would you handle edge cases such as overlapping reservations or invalid user input? What database technology would you use and why?

Uber

Describe a time you disagreed with your team members.