Notes to the Reader of Bjarne Stroustrup's Programming: Principles and Practice Using C++, 2nd Edition
- “When the terrain disagrees with the map, trust the terrain.”
- —Swiss army proverb
This chapter is a grab bag of information; it aims to give you an idea of what to expect from the rest of the book. Please skim through it and read what you find interesting. A teacher will find most parts immediately useful. If you are reading this book without the benefit of a good teacher, please don’t try to read and understand everything in this chapter; just look at “The structure of this book” and the first part of the “A philosophy of teaching and learning” sections. You may want to return and reread this chapter once you feel comfortable writing and executing small programs.
0.1 The structure of this book
- 0.1.1 General approach
- 0.1.2 Drills, exercises, etc.
- 0.1.3 What comes after this book?
0.2 A philosophy of teaching and learning
- 0.2.1 The order of topics
- 0.2.2 Programming and programming language
- 0.2.3 Portability
0.3 Programming and computer science
- 0.4 Creativity and problem solving
- 0.5 Request for feedback
- 0.6 References
- 0.7 Biographies
0.1 The structure of this book
This book consists of four parts and a collection of appendices:
- Part I, “The Basics,” presents the fundamental concepts and techniques of programming together with the C++ language and library facilities needed to get started writing code. This includes the type system, arithmetic operations, control structures, error handling, and the design, implementation, and use of functions and user-defined types.
- Part II, “Input and Output,” describes how to get numeric and text data from the keyboard and from files, and how to produce corresponding output to the screen and to files. Then, it shows how to present numeric data, text, and geometric shapes as graphical output, and how to get input into a program from a graphical user interface (GUI).
- Part III, “Data and Algorithms,” focuses on the C++ standard library’s containers and algorithms framework (the STL, standard template library). It shows how containers (such as
map) are implemented (using pointers, arrays, dynamic memory, exceptions, and templates) and used. It also demonstrates the design and use of standard library algorithms (such as
- Part IV, “Broadening the View,” offers a perspective on programming through a discussion of ideals and history, through examples (such as matrix computation, text manipulation, testing, and embedded systems programming), and through a brief description of the C language.
- Appendices provide useful information that doesn’t fit into a tutorial presentation, such as surveys of C++ language and standard library facilities, and descriptions of how to get started with an integrated development environment (IDE) and a graphical user interface (GUI) library.
Unfortunately, the world of programming doesn’t really fall into four cleanly separated parts. Therefore, the “parts” of this book provide only a coarse classification of topics. We consider it a useful classification (obviously, or we wouldn’t have used it), but reality has a way of escaping neat classifications. For example, we need to use input operations far sooner than we can give a thorough explanation of C++ standard I/O streams (input/output streams). Where the set of topics needed to present an idea conflicts with the overall classification, we explain the minimum needed for a good presentation, rather than just referring to the complete explanation elsewhere. Rigid classifications work much better for manuals than for tutorials.
The order of topics is determined by programming techniques, rather than programming language features; see §0.2. For a presentation organized around language features, see Appendix A.
To ease review and to help you if you miss a key point during a first reading where you have yet to discover which kind of information is crucial, we place three kinds of “alert markers” in the margin:
- Blue: concepts and techniques (this paragraph is an example of that)
- Green: advice
- Red: warning
0.1.1 General approach
In this book, we address you directly. That is simpler and clearer than the conventional “professional” indirect form of address, as found in most scientific papers. By “you” we mean “you, the reader,” and by “we” we refer either to “ourselves, the author and teachers,” or to you and us working together through a problem, as we might have done had we been in the same room.
This book is designed to be read chapter by chapter from the beginning to the end. Often, you’ll want to go back to look at something a second or a third time. In fact, that’s the only sensible approach, as you’ll always dash past some details that you don’t yet see the point in. In such cases, you’ll eventually go back again. However, despite the index and the cross-references, this is not a book that you can open to any page and start reading with any expectation of success. Each section and each chapter assume understanding of what came before.
Each chapter is a reasonably self-contained unit, meant to be read in “one sitting” (logically, if not always feasible on a student’s tight schedule). That’s one major criterion for separating the text into chapters. Other criteria include that a chapter is a suitable unit for drills and exercises and that each chapter presents some specific concept, idea, or technique. This plurality of criteria has left a few chapters uncomfortably long, so please don’t take “in one sitting” too literally. In particular, once you have thought about the review questions, done the drill, and worked on a few exercises, you’ll often find that you have to go back to reread a few sections and that several days have gone by. We have clustered the chapters into “parts” focused on a major topic, such as input/output. These parts make good units of review.
Common praise for a textbook is “It answered all my questions just as I thought of them!” That’s an ideal for minor technical questions, and early readers have observed the phenomenon with this book. However, that cannot be the whole ideal. We raise questions that a novice would probably not think of. We aim to ask and answer questions that you need to consider when writing quality software for the use of others. Learning to ask the right (often hard) questions is an essential part of learning to think as a programmer. Asking only the easy and obvious questions would make you feel good, but it wouldn’t help make you a programmer.
We try to respect your intelligence and to be considerate about your time. In our presentation, we aim for professionalism rather than cuteness, and we’d rather understate a point than hype it. We try not to exaggerate the importance of a programming technique or a language feature, but please don’t underestimate a simple statement like “This is often useful.” If we quietly emphasize that something is important, we mean that you’ll sooner or later waste days if you don’t master it. Our use of humor is more limited than we would have preferred, but experience shows that people’s ideas of what is funny differ dramatically and that a failed attempt at humor can be confusing.
We do not pretend that our ideas or the tools offered are perfect. No tool, library, language, or technique is “the solution” to all of the many challenges facing a programmer. At best, it can help you to develop and express your solution. We try hard to avoid “white lies”; that is, we refrain from oversimplified explanations that are clear and easy to understand, but not true in the context of real languages and real problems. On the other hand, this book is not a reference; for more precise and complete descriptions of C++, see Bjarne Stroustrup, The C++ Programming Language, Fourth Edition (Addison-Wesley, 2013), and the ISO C++ standard.
0.1.2 Drills, exercises, etc.
Programming is not just an intellectual activity, so writing programs is necessary to master programming skills. We provide two levels of programming practice:
- Drills: A drill is a very simple exercise devised to develop practical, almost mechanical skills. A drill usually consists of a sequence of modifications of a single program. You should do every drill. A drill is not asking for deep understanding, cleverness, or initiative. We consider the drills part of the basic fabric of the book. If you haven’t done the drills, you have not “done” the book.
- Exercises: Some exercises are trivial and others are very hard, but most are intended to leave some scope for initiative and imagination. If you are serious, you’ll do quite a few exercises. At least do enough to know which are difficult for you. Then do a few more of those. That’s how you’ll learn the most. The exercises are meant to be manageable without exceptional cleverness, rather than to be tricky puzzles. However, we hope that we have provided exercises that are hard enough to challenge anybody and enough exercises to exhaust even the best student’s available time. We do not expect you to do them all, but feel free to try.
In addition, we recommend that you (every student) take part in a small project (and more if time allows for it). A project is intended to produce a complete useful program. Ideally, a project is done by a small group of people (e.g., three people) working together for about a month while working through the chapters in Part III. Most people find the projects the most fun and what ties everything together.
Some people like to put the book aside and try some examples before reading to the end of a chapter; others prefer to read ahead to the end before trying to get code to run. To support readers with the former preference, we provide simple suggestions for practical work labeled “Try this” at natural breaks in the text. A Try this is generally in the nature of a drill focused narrowly on the topic that precedes it. If you pass a Try this without trying — maybe because you are not near a computer or you find the text riveting — do return to it when you do the chapter drill; a Try this either complements the chapter drill or is a part of it.
At the end of each chapter you’ll find a set of review questions. They are intended to point you to the key ideas explained in the chapter. One way to look at the review questions is as a complement to the exercises: the exercises focus on the practical aspects of programming, whereas the review questions try to help you articulate the ideas and concepts. In that, they resemble good interview questions.
The “Terms” section at the end of each chapter presents the basic vocabulary of programming and of C++. If you want to understand what people say about programming topics and to articulate your own ideas, you should know what each means.
Learning involves repetition. Our ideal is to make every important point at least twice and to reinforce it with exercises.
0.1.3 What comes after this book?
At the end of this book, will you be an expert at programming and at C++? Of course not! When done well, programming is a subtle, deep, and highly skilled art building on a variety of technical skills. You should no more expect to be an expert at programming in four months than you should expect to be an expert in biology, in math, in a natural language (such as Chinese, English, or Danish), or at playing the violin in four months — or in half a year, or a year. What you should hope for, and what you can expect if you approach this book seriously, is to have a really good start that allows you to write relatively simple useful programs, to be able to read more complex programs, and to have a good conceptual and practical background for further work.
The best follow-up to this initial course is to work on a real project developing code to be used by someone else. After that, or (even better) in parallel with a real project, read either a professional-level general textbook (such as Stroustrup, The C++ Programming Language), a more specialized book relating to the needs of your project (such as Qt for GUI, or ACE for distributed programming), or a textbook focusing on a particular aspect of C++ (such as Koenig and Moo, Accelerated C++; Sutter’s Exceptional C++; or Gamma et al., Design Patterns). For more references, see §0.6 or the Bibliography section at the back of the book.
Eventually, you should learn another programming language. We don’t consider it possible to be a professional in the realm of software — even if you are not primarily a programmer — without knowing more than one language.