Round 1:
Design Snakes Games. With every 5 steps, the snake will grow by 1

Round 2:
Given files and their size and collection. Return the top 5 collections on the basis of total file size in the collection. Also, some files may not have a collection at all.
The Interviewer was judging on the basis of everything the function name, class name, attribute name, the design patterns and the input format as well.