I have applied for the SDE-2 role through Instahyre. Got a call from HR and then a test link was sent to me.
Round 1(Online Assessment): Online Assessment on HackerEarth.
- There were three DS-Algo questions. Questions are categorized based on various levels: Easy, Medium, and Hard.
- I have solved 2 questions with all test cases being passed and one partially solved because some of the test cases were giving Time Limit Exceed.
- I got a call from HR of Paypal after 3-4 days of this test.
Round 2(DS Algo & Problem Solving): This round was totally focused on Data structure & algorithms. There were two questions asked and some basic Java Questions.
- LCA of Binary Tree
- 0/1 Knapsack
- Working of ConcurrentHashMap
- Generics in Java, ThreadLoacal, What is Future object and how Future is different from CompletableFuture
Round 3(LLD+Problem Solving):
- Design a Cache that can store value against a key. Also, the cache eviction policy and capacity should be configurable. You need to follow SOLID principles and Design Patterns while designing the same.
Later, the interviewer asked that if I have to take care of a Multi-Threaded environment – How would I do that? (only explanation was required). - Remove duplicates from given LinkedList.
Round 4(System Design):
- Questions from my resume
- Design Whatsapp-like messaging app.
Too many questions were asked about the choices you make, tradeoffs, network protocols you will use for real-time communication and how can we extend this to implement end-to-end encryption.
Round 5(Techno Managerial): This was also a technical round.
- Clone a graph (Deep Copy)
- Design a scalable service that stores some secret pieces of information.
- Project-related questions.
- Cultural fit and behavioral questions.
Round 6(HR):
- Cultural fit and behavioral questions.
- CTC and Stocks discussions
Result: SELECTED