The application 'main.cxx' performs the following functions:
a) It reads a list of ASCII words from STDIN, a word per input line, terminated by the word 'end'.
b) It removes the duplicates, sorts the words alphabetically, and prints them with the number of how many times each word was encountered.
c) Then it repeatedly asks the user to enter a word and tries to look it up in the word list which was entered initially. It terminates when it encounters EOF.