I was selected to interview for Paytm Money from Instahyre. The job profile was Senior Software Engineer

All the rounds were on Google Meet and the interview lasted about 1 hour.

Interview Round - 1 (DS/Algo Round)
It started with a general introduction and then jumped to some DSA problems.

Problem 1: Given two Linked lists merge at a point, find and return this point.
Problem 2: Rainwater trapping problem

He then concluded the round by asking some questions on spring boot.

Interview Round - 2 (Java Round)
This was more of a mixed technology-based round.

Problem 1: Given two numbers as arrays, return their sum.
Problem 2: Difference between synchronized HashMap and ConcurrentHashMap.
Problem 3: OOPS concepts with code examples
Problem 4: Write code examples for observer pattern and factory pattern.

Interview Round - 3 (Design Round)
This round revolved around designing.

Problem 1: Explain the architecture of the project you’re working on
Problem 2: Let’s assume some of you API endpoint is giving very high latency, how will you resolve it.
Problem 3: Design Parking Lot System

Final verdict - Selected