CareerCup

With one pointer and additional memory to store each node traversed we can find out if linked list has loop. This is O(n2) solution and O(n) space.

Your solution will work but can be improved by only pushing first half of elements on stack. Middle of linkedlist can be found using slow and fast runner approach. Once we reach at the middle we start comparing element pointed by slow pointer and popping element on top of stack.

Existing class hierarchy can be easily retrofitted to add new behavior using interfaces. Interfaces allows to define mixed behaviors. Interfaces allows constructions of non-hierarchial frameworks.
Abstract classes are easy to evolve. Adding new behavior to abstract classes is simpler than interfaces.
Prefer abstract classes if simplicity is more important than flexibility.

It is worth reading Item 18 in Effective Java to understand why to prefer interfaces over abstract classes.

@ duskandawn your theory applies to only accessing protected members but Mallika is right about object creation when constructor is protected.

yes. It is about improving performance of sql query but not specific to any database.

Question was not posted to know answer, but what can be expected in interview.

BTW YOU ARE WELCOME!!

ps -ef | grep <<process_name>>

This gives us list of process matching the process_name keyword for all users along with process id. Use this process_id to kill using command below,

kill -9 <<process_id>>

MVC de-couples the models from views by adding controller layer between them which allows to modify view and model without affecting each other. We can also have different view implementation calling same model layer through controller. Controller handles any request coming from view and forward it to appropriate model. Selecting model to forward request is completely design decision. Model generally but not necessarily is comprised of service layer or data access layer.

+1
Solution works out for almost all cases, but length check can make this test case to fail "He bugs Gore" & "George Bush", even though they are anagram if spaces are ignored. I guess this can be question to interviewer.