Efficient File Parsing

Given a file whose name is passed as an argument to a program. Count the number of distinct unique words in it.

Constraints

• File is guaranteed to contain only 'a'..'z' and space characters in ASCII encoding.
• Should be able to handle large inputs (e.g. 32 GiB).
• You can assume that all unique words fit into memory when using the data structure of your choice.
• The solution must utilize all available CPU resources.

Quick Start

$ make -Bj
$ ./efp <file>