Coding test was about Java string manipulation. video response:Why BlackRock? why softeware engineer? Why BlackRock choose you? On site interview questions: 1. Reserve a string in place 2. Write a method that convert decimal to binary 3. What’s is Singleton 4. What are differences between Array and ArrayList in Java 5. If you are going to design a phone directory, what data structure will you use? 6. Calculates Fibonacci number Do it with recursion, and without recursion: e.g: I have an array, [3, 5, 4 ]. Return 3rd, 5th, and 4th Fibonacci number and store in an array and return it. What’s complexity of your algorithm? 7. Return size of last word in a sentence. E.g.: String s = “Hello Wang”, return 4 String s2 = “Hello ”, return 5 String s3 = “”, return 0 8. Input is a number > 9. Write a program stops when sum of all digits is less than 10. e.g. 38, 3+8 = 11; 1+1 = 2, stop 9. What are differences between String, StringBuilder and StringBuffer in Java Hope it helps :)