The first stage was a coding exercise with an engineer. One question was easy and could be solved with hash maps, and the second was similar to Trapping Rain Water on LeetCode.

I then had four interviews in one day:

• Data Structures: This was a purely theory-based interview on different Java data structures, starting with List, Array, and then Map and HashMap, and LRU Cache.
• System Design: In this interview, I was asked about my current project at work and the system design decisions made.
• SDLC interview: Various questions on my experiences, trade-offs between different database options, and how to achieve software availability, scalability, etc.
• Interview with the team director: A conversation about my motivations and what I am looking for in my next role.

The most frustrating thing was that I got no feedback on the interviews despite giving my entire day to them. I reached out to the recruiter and TA person twice for it.

How does HashMap work internally in Java?

What are the different implementations of List?