Software Development Engineer, Business Data Technologies

Amazon

You are given an array of servers represented by their processing power. You want to join consecutive servers together to form larger, more powerful servers. You can only join server i with server i+1 if the processing power of server i+1 is strictly greater than the processing power of server i. This joining process can cascade, meaning that if you join i and i+1, and the new combined processing power is less than i+2, you can then join the combined server with i+2, and so on. The goal is to maximize the number of these larger servers. For example: Consider the array [1, 2, 3, 4, 5]. You can join 1 and 2 to form 3. Then you can join 3 and 3 to form 6. Then you can join 6 and 4 to form 10. Finally, you can join 10 and 5 to form 15, resulting in one server with processing power 15. Consider the array [5, 4, 3, 2, 1]. You cannot join any servers because the processing power is always decreasing. Consider the array [1, 3, 2, 4, 1, 5]. You can join 1 and 3 to get 4. You cannot join 4 and 2. You can join 2 and 4 to get 6. You cannot join 6 and 1. You can join 1 and 5 to get 6. The final servers will be [4, 6, 6]. Write a function that takes an array of integers representing server processing powers and returns the final array of server processing powers after performing all possible joins.

Amazon

Elevator System Design Design an elevator system for a 20-story building. Consider the following: Number of Elevators: How many elevators would you recommend, and why? Elevator Capacity: What should be the capacity (in terms of weight and number of people) of each elevator? Algorithm for Request Handling: Describe an algorithm for efficiently handling elevator requests, considering factors like minimizing wait times and energy consumption. Example: Should the elevator always go to the closest floor first, or should it consider the direction of travel? Edge Cases and Error Handling: How would you handle edge cases such as: Elevator malfunction? Power outage? Overweight elevator? Simultaneous requests from multiple floors? Optimization: How can you optimize the system for peak hours (e.g., morning rush hour, lunch break)? Consider strategies like: Designating specific elevators for up/down travel during peak times. Implementing a learning system that adapts to usage patterns. User Interface: Describe the user interface (both inside the elevator and on each floor) and how it provides feedback to users. Scalability: How would the design change for a 50-story or 100-story building? What are the limitations of your current design? Explain your design choices and justify them with appropriate reasoning. Focus on creating a robust, efficient, and user-friendly elevator system.

Amazon

Describe a time when a plan did not go as expected.