For Backend Engineer role
Zero Round:
Given list of cities and theaters list, design and develop a ticket booking web application.
It should have following features:
- Only one person can book the seat per show. Handle concurrent requests coming for same seat.
- If a seat to selected and not booked then that should be unblocked after 10 minutes.
- Expose API to show list of available, blocked, and booked seats for a theater
First Round:
- Interviewer reviews design, code and asks to a another features.
- Coding problem: Given a large matrix size of 10^18X10^18 and list sub tables with top-left and right bottom coordinates and number filled in those tables. Illustration below. Find the coordinates of number ‘n’.
Second Round:
- Design Question: Design an application where client wants uploads million records, validate and insert into db.
Conditions:
- There should not be any loss of data.
- Handle if DB goes down temporarily
- Questions around design patterns.
Third Round:
- Design “Executor Service”
- How threads are managed in web server?
- What are the technical challenges you faced in your previous company?
- Different garbage collections algorithms?