Given a file, find the ten most frequently occurring words as efficiently as possible

Question

This is apparently an interview question (found it in a collection of interview questions), but even if it\'s not it\'s pretty cool.

We are told to do this efficien

Answer 1

Depending on the size of the input data, it may or may not be a good idea to keep a HashMap. Say for instance, our hash-map is too big to fit into main memory. This can cause a very high number of memory transfers as most hash-map implementations need random access and would not be very good on the cache.

In such cases sorting the input data would be a better solution.