Overview...

This lab is a simple example of data scraping. Getting data onto your screen,
then collecting and processing the data. We will scrape data from Odin.

Start with your 3350/6/bugsbunny.cpp program.

   • Write a program on Odin named /3350/8/uvlab8.cpp

   • Please include a Makefile that builds your program(s).




Program details

We are writing a Linux utility program.

We want to know how many users are logged in once, twice, 3-times, 4-times, etc.

Use the Linux w utility to create a file, then scrape the file.

sample output...


$ ./uvlab8

Odin current login statistics
-----------------------------
 1 login:  12 users
 2 logins:  5 users
 3 logins:  1 user
 5 logins:  1 user




One strategy to try:
   Put the file records into an array.
   Sort the array.
   Read through the sorted array.
   Count how many reads until the username is different.
   That is a user logged in 'count' times.
       Use 'count' as an index into a hash table.
       Increment the hash table at that index.
   Continue through the sorted array.
   Display the output.


Using the strategy above...
    1 2 3 5  are indexes of a hash table
    12 5 1 1 are the values stored at those array indexes.


Rules...
Do not use the STL, vectors, <algorithm>, etc.
If you find any code online...
   1. Put the URL in a comment.
   2. Briefly explain why you could not write the code yourself.


Program files to be collected...

   3350/8/uvlab8.cpp
   3350/8/Makefile




Unit test

1. Create a data file with known values.

   This file will contain data in a structure similar to the file
   your program will construct for the live Odin data.

   To do this Unit Test, run your program like this:

   ./utest myfile.txt

   When your program sees a command-line file name, it will use that
   file for a test rather than scraping live data from Odin server.

   You must put this functionality in a second executable.

   This compile option will activate your Unit Test...

   -D UNIT_TEST

   Isolate all unit test functionality from your production program
   using #define pre-processor directives.


   Gordon will test your program with live data, and unit-test file input.