The program:

     use-query-handle

takes an argument that specifies the file to read.  It also
reads the standard input iterating with the user for words 
to find in the file.  
The file 'data/Alice_story' is the simple story used for queries
presented in the book

The program:

     swap

reads a pair of integers from the standard input.  The file
'data/swap' can be used with this program.

The remaining programs are self-contained. 
They write to the standard input but do no input.

