WWW-TRAKLA

A Web-Based System for Teaching Algorithms and Data Structures

Background

Understanding data structures and the algorithms manipulating them is an integral part of elementary computer science education. To properly understand the operation of particular algorithm the student must apply it in a real problem. Usually, this has meant writing a program that implements the desired algorithm. However, being able to implement an algorithm does not necessarily mean that the student understands how it actually works. There is a lot of sample code available that can be used with little or no modification. And much of the time is spent on trivial programming details which do not concern the actual algorithm.

At the Laboratory of Information Processing Science at Helsinki University of Technology, we noticed that students of the basic course of data structures and algorithms (CS7) learn better by simulating the algorithms manually. Students have to solve a number of homework exercises by showing how the data structures change in successive steps during the execution of the algorithm. Exercises covers basic data structures, different sorting methods, dictionaries, string manipulation and graph algorithms.

TRAKLA-system distributes homework exercises and evaluates the student's answers automatically. The exercises are individually tailored for each student so that copying the answers from others is not possible. There are two possible ways to send answers back to the TRAKLA server. The old method is to solve the problems by paper and pencil and send the answers in a specified format by email to TRAKLA. The other way is to use Web-based interactive graphical editor TraklaEdit. The Web-based environment uses the hypermedia properties of WWW and the actual editor is coded in Java-language. The whole Web-based system is called WWW-TRAKLA.

The main goal was to achieve a flexible and platform independent learning environment. With Java-compatible Web-browsers such a system is possible to implement. All the features of TRAKLA system (i.e. registration, exercises, gradings and so on) are possible to implement in Web. Thus, the student sees the whole system through the Web.

The whole system is available through the home-pages of the course in Tik-76.122 Data Structures and Algorithms.

Most of the pages are written both in finnish and in english. Please, feel free to visit the pages. If you are interested in testing the system also by solving the exercises, take contact to the author. In order to fully use the editor and all of it's features a registration is needed. A guest student number with your name and email address could be generated.

If you have comments or suggestions, email me at tred@cs.hut.fi