Started with a HackerRank test with a mix of objective-type questions and a couple of programming questions.

After the HackerRank test, they made candidates wait for 4 hours to start interviewing for the next round. Unprofessional and ad hoc approach by HR.

The interviewer didn't seem interested in taking the interview; he was probably tired and wanted to finish off quickly without even trying to understand the candidate's background. The interviewer had already decided not to consider my profile; he seemed uninterested and wanted to wrap up the interview quickly.

Code to insert into BST.