1) time complexity of a Balanced Binary Search Tree (BBST). recursive function to calculate height of a binary tree in java 2) What is AVL tree 3) An array whose frequency is greater than n/2 where n is length of array. for example: {1,2,1} output is 1 4) brute force approach 5) try { System.exit(0); } finally { System.out.println("finally"); } output? 6) Why 0 in System.exit(0) 7) Difference Final, finally, finalize 8) final List a = new ArrayList<>(); a.add("Hello"); a.add("World"); What will be the output 9) What is the use of final in Collection 10) How to make object final 11) String s = "abc"; s+="def"; output? 12) What is spring boot 13) Difference between @RestController and @Controller 14) What is @Component and @ComponentScan 15) Spring boot application if we want a @Service class to run, is it important to mark it with @Service 16) Spring AOP 17) @Transactional annotation and Why 18) What is ACID properties 19) What is dependency injection in spring boot