1. Reverse each word in the sentence and return the sentence. 2. Different ways of finding element in an array. 3. Balance paranthesis 4. Quick sort algorithm 5. Can you use class instance as key in HashMap? does it compile? any dis-advantages? 6. Given an input which could be data stream. You have matching data which you need to match that input data stream with this matching data and return the input from data stream if there is a match. Few constraints within it.