Can we do Quick sort with n logn worst case complexity?

Well, Yes we can bring it down to O(nlogn). All the algorithms I have seen that try to bring this down are based on choosing your pivot point. If you can "intelligently" choose your pivot point it can be brought down.

Well "modify" is a rather subjective word here. There are a number of ways you can augment quicksort to make it run in O(n log n). Whether or not you could still call it a quick sort is to be determined.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.