Pre-interview Rounds

1st Round: This was an MCQ round with questions in four sections: verbal communication, aptitude, coding, and OS & DBMS, lasting for around 2 hours.

2nd Round: This was a coding round with 2 questions:

1. How many minimum numbers of bits should be flipped in a string containing 0s and 1s such that 0s and 1s are alternate?
2. If the first letter in a string is capital, change the entire string to capital letters; otherwise, change the entire string to small letters.

Face-to-Face Rounds

All interviewers were friendly and asked about data structures and general programming. Each interviewer asked if I had any questions at the end. Students were evaluated based on their thinking ability, programming skills, attitude, and communication in each round.

1st Round The interviewer asked me to explain two of my projects. Afterward, he asked me to write a program for the Fibonacci series and then for finding anagrams in a sentence. Complete code was expected, but each line was not scrutinized. If you can explain it correctly and confidently, it should be good enough. He also asked some basic Java questions. He then posed a question about a matrix containing 0s and 1s and how to change rows and columns to 0s. He later asked how I would declare a multidimensional hashmap.

2nd Round The level of technical questions increased in this round. Complete code was expected. He started by asking about my projects. Then he began asking about different data structures and the advantages of a linked list. He asked how I would find a loop in a linked list and its starting point. He then asked a question about stock prices stored in an array: how to find the time to buy and sell stock to maximize profit (I first gave a solution requiring multiple traversals, which he asked me to optimize into a single traversal). He then asked how I would implement a random function without built-in functions. He then asked how I would develop a multilevel parking system with different vehicle limits at each level, designed to show if it's full or not. Finally, he asked how I would print a matrix in a zigzag way.

3rd Round The interviewer asked me to start by introducing myself. He asked me to explain any one of my projects that I liked. I explained the project I did about generating movie recommendations with the full logic. He then asked for the program to convert decimal into binary. Later, he asked me to perform a level order traversal of a BST. I provided a recursive solution, but he was not satisfied and asked me to reduce the number of traversals, so I suggested using a queue, which he accepted. He then asked a query: in a table consisting of author ID, book name, year, and cost, how can I retrieve the number of authors who sold more than 3 books in a year? He also asked general Java concepts like inheritance and polymorphism. He then asked questions like, "Tell me about your family," and "Why Oracle?"

Finally, they announced the results at around 9:15 PM. Twenty-five students were selected.

Stock prices are stored in an array. How to find the time to buy and sell the stock so as to maximize the profit?