Cognizant interview question

We had 3rounds. Round1: typical aptitude + programming basic (this was all MCQ) Round2: interview round. In this I was asked to code 'reverse a string' & explain how a heap sort works. Apart from this I was asked my subjective computer questions from SQL, Networking, DBMS, OS (all very basic) Round3: this was more of HR + documents providing rounds and less technical. Was asked 3basic or full form type question from a technical recruiter.