Oberon examples from Algorithms and Data Structures by N. Wirth

This is a collection of examples from the book. I use this project to test and play with examples w/o need to modify them from Oberon to anything else. The book doesn't cover Oberon syntax and its programming model. But it's available in Internet, like that.

I used initially Excelsior's XDS SDK for Modula-2/Oberon-2. Which was a good start, but unfortunately I couldn't get there debugger to work on Windows 10. So I switched to Oxford Oberon-2 Compiler which can be found >here.

Algorithms covered

Searching:

• Linear
• Binary

Sorting:

• Straigt Insertion
• Binary Insertion

String:

• KMP search
• BM search

Advanced Sorting:

• Shell Sort
• Heap Sort
• Quick Sort

Sorting Sequences (Files):

• Merge Sort
• Natural Merging
• Balanced Merge
• Polyphase Merge

Recursion:

• Hilbert and Sierpinski curves
• Knight's Tour
• Eight Queens
• Stable Marriage

Differences from original code

• Arrays are usually fixed size in the book. Though here size is determined in runtime using LEN() command
• Book introduces notion of NULL-terminated strings but doesn't use them in string search examples. Here all strings are NULL-terminated and there length is computed in runtime. Though usually array size is 255.
• All operations on standard input/output are based on Oberon-2 implementation. For example, Text.Scan() is replaced with In.Int() and Out.Int() is used instead of Text.WriteInt().
• Wirth's module "Files" renamed to "Filez" because it clashes with OBC's standard module. Though interface remains the same.

Building

XDS projects (folders were *.prj files exists) on Windows and Linux

1. Download and install XDS SDK from https://www.excelsior-usa.com/xds.html#downloads
2. Add xc executable to your search path.
3. Use xc to compile a project. For example: xc =project exp/exp.prj

OBC projects on Mac and Linux

1. Download and install Oxford Oberon-2 compiler from here
2. Add obc executable to your search path
3. Use make to compile module.