This intermediate-level treatment surveys data structures used in programming, concepts of programming in Modula-2, and algorithms useful for manipulating data structures. Emphasizes programming style and offers a wealth of examples, including complete, real-world programs. Approach to developing algorithms is very clear, making it easy to apply the principles of good programming. Chapters cover elementary Modula-2, essential language features, fundamental abstract data types, linked lists, binary trees, sorting algorithms, applications, and additional data structures. Each chapter contains a review section, practice test, and programming problems.
Offers a modern treatment of data structures featuring the use of abstract data types and generics. Designed for freshman/sophomore courses in data structures and/or advanced programming. Introduces data structure concepts before their implementation and details the salient differences between Pascal and Modula-2. Advanced topics include virtual hashing, balanced tress, and B trees.
This text is an introduction to programming in general, and a manual for programming with the language Modula-2 in particular. It is oriented primarily towards people who have already acquired some basic knowledge of programming and would like to deepen their understanding in a more structured way. Nevertheless, an introductory chapter is included for the benefit of the beginner, displaying in a concise form some of the fundamental concepts of computers and their programming. The text is therefore also suitable as a self-contained tutorial. The notation used is Modula-2, which lends itself well for a structured approach and leads the student to a working style that has generally become known under the title of structured programming. As a manual for programming in Modula-2, the text covers practically all facilities of that language. Part 1 covers the basic notions of the variable, expression, assignment, conditional and repetitive statement, and array data structure. Together with Part 2 which introduces the important concept of the procedure or subroutine, it contains essentially the material commonly discussed in introductory programming courses. Part 3 concerns data types and structures and constitutes the essence of an advanced course on programming. Part 4 introduces the notion of the module, a concept that is fundamental to the design of larger programmed systems and to programming as team work. The most commonly used utility programs for input and output are presented as examples of modules. And fmally, Part 5 covers facilities for system programming, device handling, and multiprogramming.
Modula-2 is a simple yet powerful programming language that is suitable for a wide variety of applications. It is based on Pascal, a successful programming language that was introduced in 1970 by Niklaus Wirth. During the 1970's Pascal became the most widely taught programming language and it gained acceptance in science and industry. In 1980 Dr. Wirth released the Modula-2 program ming language. Modula-2 is an evolution of Pascal. It improves on the successes of Pascal while adding the MODULE - a tool for ex pressing the relations between the major parts of programs. In ad dition Modula-2 contains low-level features for systems program ming and coroutines for concurrent programming. Programming languages are important because they are used to express ideas. Some programming languages are so limited that certain ideas can't be easily expressed. For example languages that lac k floating point arithmetic are inappropriate for scientific com putations. Languages such as Basic and Fortran that lack recur sion are unsuitable for text processing or systems programming. Sometimes a programming language is useable for a certain appli cation but it is far from ideal. A good example is the difficulty of writing large programs in pure Pascal. Pascal is a poor language for large jobs because it lacks facilities for partitioning a program viii Preface 6
Source Code Availability All of the source code found in this volume, and some that is not, is available from the author at a nominal fee. The author is interested in learning of any errors that may be found, though care has been taken in the construction of the modules to minimize these. The author is also interested in other comments, suggestions, recommendations, questions or experiences with the use of these modules. Contact the author through the following address: Modula-2 Software c/o Springer-Verlag 815 De La Vina St. Santa Barbara, CA 93101 As of February 1988, source code is available on 3.5" Macintosh diskettes (800K HFS format) for the TML Modula-2 compiler for MPW and the Mac METH Modula-2 compiler from ETH Ziirich. 1 Specification Requirements for specification of procedure and data abstractions were previously covered in Volume 1, Chapter 2. A summary is provided of the specification for mat used in this book. The format is adapted from that Guttag and Liskov [10] developed for the CLU language. It consists of relatively few constructs, is semi formal by providing a rigorous definition of the syntax and semantics of opera tions, and it provides powerful facilities for defining abstract data types. 1.1 Specification of Procedure Abstractions Specification of a procedure requires a full description of syntax and semantics. Syntax the name of the procedure by name, the name and type of each ar gument or result, and the order in which the arguments and results occur.
This text is an introduction to programming in general, and a manual for programming with the language Modula-2 in particular. It is oriented primarily towards people who have already acquired some basic knowledge of programming and would like to deepen their understanding in a more structured way. Neveltheless, an introductory chapter is included for the benefit of the beginner, displaying in a concise form some of the fundamental concepts of computers and their programming. The text is therefore also suitable as a self-contained tutorial. The notation used is Modula-2, which lends itself well for a structured approach and leads the student to a working style that has generally become known under the title of structured programming. As a manual for programming in Modula-2, the text covers practically all facilities of that language. Part 1 covers the basic notions of the variable, expression, assignment, conditional and repetitive statement, and array data structure. Together with Palt 2 which introduces the important concept of the procedure or subroutine, it contains essentially the material commonly discussed in introductory programming courses. Part 3 concerns data types and structures and constitutes the essence of an advanced course on programming. Palt 4 introduces the notion of the module, a concept that is fundamental to the design of larger programmed systems and to programming as team work. The most commonly used utility programs for input and output are presented as examples of modules.
MODULA-2 is a new programming language which was created by Niklaus Wirth of the Swiss Federal Institute of Technology (ETH) in Zurich. The lan guage is derived from PASCAL: it includes all aspects of PASCAL and some times improves on them. Moreover, MODULA-2 includes the important "mod ule" concept, as well as multiprogramming capabilities and a way of implemen ting low-level software in an elegant manner. In summary, MODULA-2 may be used equally well as a general-purpose programming language and as a system implementation language. MODULA-2 provides the programmer with a good way of writing high quality software. In particular, modules are powerful tools for achieving modularity, reliability, readability, extensibility, reusability and ma chine-independence. This book presents the complete MODULA-21anguage from the beginning. Each topic is presented by means of numerous examples and each concept is justified. The syntax of the language is explained using syntactic diagrams. This book is not a reference manual for MODULA-2, but a textbook from which the student can learn the language progressively. The most important con cepts (i.e. procedures, modules and data structures) are explained in great detail and methodological aspects are also emphasized. Beginning in the first chapter, the student may execute his/her own pro grams. Program examples in this book have been executed on several machines (APPLE II, IBM PC and VAX 11/780) and they may be taken as a basis for stu dents.
