Bkash Software Engineer interview questions

I was hired through a campus recruitment program. The whole process is of 4 steps. Step 1 : A written exam was taken for the screening round. They ask basic CS fundamentals questions on OS, Networking, Database, SOLID principals, Design pattern. But the thing is, they don't ask you explain this or that. They came up with an situation and tell you to solve it using the knowledge you have ( say are you going to use design pattern for this, if yes then what would be the pattern and why). There were 5-6 programming questions, mostly on linked list and arrays. Basic leetcode easy questions. These are really important. So the catch was that they provide minimal time for the exam. So be careful with the time management and be very good when you are writing the solutions. Step 2 : Technical round : They asked me what are my favourite subjects in my university and ask questions accordingly. The whole technical round was around 45-50 min. They mainly wanted to know if you have the basic theoretical understanding of the CS fundamentals. Say for example how the program runs, how OS maintain multiple threads, why do we do indexing, why OOP is necessary, what are the drawbacks of OOP and many questions like this. Step 3: The coding round. They invited me to their office for the round. They gave me 2 problems to solve. Difficulty was leetcode medium for both the questions. Time was 1 hr. And then they ask follow up questions. So the whole coding round was about 1.5 hr. Step 4 : HR & Dept Head round. The dept head asked 3 questions. And then the HR ask a few fundamental questions like what is my future plan, am I going to stay or not.