I had four rounds of interviews.

1. Technical Phone Screen: An average technical round revolving around data structures and algorithms. This was a screening round for the further interviews.

2. Coding Round: I had to implement a map data structure that would intake an array and use functions to create a mapping for that array. More functions could be added to the class, and we had to implement the mapping lazily. This involved storing the mapping in a function or an array of functions, along with an index function to check the index of a given value in the array. I did pretty well, in my opinion, but the interviewer told the manager that I couldn't complete the initial implementation and provided some negative feedback.

3. Algorithm Round: I implemented a path-finding algorithm in a 2D array using BFS. I received positive feedback from the interviewer.

4. System Design Round: I had to implement a durable hashmap where put and get operations were performed, and success was guaranteed if the put function returned. A write function was created to asynchronously write updated dictionaries to the system after every 100th write. The interviewer gave positive feedback.

5. Hiring Manager: Due to the negative feedback from the second round, they declined to extend an offer and advised me to re-apply after eight months.

(System Design)

Design a key-value store that is durable.