Summary
I interviewed for an SDE2 position at PocketPills in Gurgaon. The process involved two rounds: Data Structures/Problem Solving and System Design. Unfortunately, I was rejected after the second round.
Full Experience
I recently interviewed for an SDE2 role at PocketPills in Gurgaon. The interview process consisted of two rounds covering both technical and system design aspects.
The first round focused on Data Structures and Problem Solving. I was asked to solve the 'Gas Station' problem, which is a classic LeetCode problem. Additionally, there were several Java-specific questions covering core concepts: implementing a Singleton class, understanding the usage of final, static, transient, synchronized, and volatile keywords, and implementing an Immutable class in Java.
The second round was a System Design interview. The primary task was to design a Dropbox-like system, focusing on its High-Level Design. The key requirements included user login/logout, file upload/download (with a file size limit of 1GB), supporting 1 million daily active users, and handling one file upload per user daily. We discussed various aspects like the necessary APIs for login, logout, upload, and download. For file storage, I suggested using cloud storage like AWS S3 and discussed strategies for handling large files through chunk uploads. Security considerations included implementing user authentication using JWT and encrypting files during transfers. A follow-up question involved how to enable users to share files with other users.
Ultimately, I was rejected after completing the second round.
Interview Questions (5)
Given n gas stations along a circular route, where the amount of gas at station i is gas[i]. You have a car with an unlimited gas tank and it costs cost[i] of gas to travel from station i to station i + 1. You begin the journey with an empty tank at one of the gas stations. Return the starting gas station's index if you can travel all around the circuit once, otherwise return -1. If there exists a solution, it is guaranteed to be unique.
Explain the concept of a Singleton class and demonstrate its implementation in Java. Discuss its use cases and potential pitfalls.
Explain the purpose and usage of final, static, transient, synchronized, and volatile keywords in Java, providing examples for each.
Describe what constitutes an immutable class in Java and provide an example of how to implement one, outlining the rules and benefits.
Design a high-level architecture for a system similar to Dropbox.
Requirements:
- Users can log in and log out.
- Users can upload/download multiple files (file size limited to 1GB).
- Daily Active Users - 1M.
- User uploads 1 file daily.
- APIs for login, logout, upload, and download.
- File storage: Using cloud storage (e.g., AWS S3) and handling large files with chunk uploads.
- Security: User authentication (JWT) and encrypting files during upload/download.
- How to allow users to share files with other users?