Visa Inc. Staff Software Engineer interview questions

The hiring process to the Data Technology team in Foster city. Very nice recruiter contacted me to set up the 45 min phone screening. The process: Phone Screening with Lead software engineer, HackerRank test, on site interviews

Process took just a week. HR contacted me as she liked my LinkedIn profile. Scheduled a half an hour interview with a lead title holder and the interview got postponed twice. In this process they shared Hackerrank challenge to be solved in 3 days. So I had interview and the challenge on the same day but the interviewer was some new person. Interview Experience: Asked academic project related questions. Disadvantages of TF-IDF as the interviewer saw that term on my resume. What data structure would you use to find a the longest word starting with "CATER" when given a dictionary of words. (the words can be CATERS, CATERERS, CATERING). Output should be Catering. How do you access private variables from outside a class without using getter and setter methods. Explain about the heap and stack memories. Garbage collector is called on heap or stack? Explain about the Decorator design patter Explain about Comparator and Comparable Difference between HashMap and HashTable What is Hypervisor? Hackerrank A problem on Roy's lucky number and another problem on overloading the methods of Comparator