The Accredited Standards Committee, operating under the procedures of the American National Standards Institute (ANSI), is working to create an international standard for C++.

The ANSI standard is an attempt to ensure that C++ is portable—that code you write for Microsoft’s compiler will compile without errors, using a compiler from any other vendor. Further, because the code in this book is ANSI compliant, it should compile without errors on a Mac, a Windows box, or an Alpha.

For most students of C++, the ANSI standard will be invisible. The standard has been stable for a while, and all the major manufacturers support the ANSI standard. We have endeavored to ensure that all the code in this edition of this book is ANSI compliant.

The question inevitably arises: "Since C++ is a superset of C, should I learn C first?" Stroustrup and most other C++ programmers agree. Not only is it unnecessary to learn C first, it may be advantageous not to do so. This book attempts to meet the needs of people like you, who come to C++ without prior experience of C. In fact, this book assumes no programming experience of any kind.

C++, perhaps more than other languages, demands that the programmer design the program before writing it. Trivial problems, such as the ones discussed in the first few chapters of this book, don’t require much design. Complex problems, however, such as the ones professional programmers are challenged with every day, do require design, and the more thorough the design, the more likely it is that the program will solve the problems it is designed to solve, on time and on budget. A good design also makes for a program that is relatively bug-free and easy to maintain. It has been estimated that fully 90 percent of the cost of software is the combined cost of debugging and maintenance. To the extent that good design can reduce those costs, it can have a significant impact on the bottom-line cost of the project.

The first question you need to ask when preparing to design any program is, "What is the problem I’m trying to solve?" Every program should have a clear, well-articulated goal, and you’ll find that even the simplest programs in this book do so.

The second question every good programmer asks is, "Can this be accomplished without resorting to writing custom software?" Reusing an old program, using pen and paper, or buying software off the shelf is often a better solution to a problem than writing something new. The programmer who can offer these alternatives will never suffer from lack of work; finding less-expensive solutions to today’s problems will always generate new opportunities later.

Assuming you understand the problem, and it requires writing a new program, you are ready to begin your design.

This book makes the assumption that your computer has a mode in which you can write directly to the screen, without worrying about a graphical environment, such as the ones in Windows or on the Macintosh.

Your compiler may have its own built-in text editor, or you may be using a commercial text editor or word processor that can produce text files. The important thing is that whatever you write your program in, it must save simple, plain-text files, with no word processing commands embedded in the text. Examples of safe editors include Windows Notepad, the DOS Edit command, Brief, Epsilon, EMACS, and vi. Many commercial word processors, such as WordPerfect, Word, and dozens of others, also offer a method for saving simple text files.

The files you create with your editor are called source files, and for C++ they typically are named with the extension .CPP, .CP, or .C. In this book, we’ll name all the source code files with the .CPP extension, but check your compiler for what it needs.

NOTE: Most C++ compilers don’t care what extension you give your source code, but if you don’t specify otherwise, many will use .CPP by default.

DO use a simple text editor to create your source code, or use the built-in editor that comes with your compiler. DON’T use a word processor that saves special formatting characters. If you do use a word processor, save the file as ASCII text. DO save your files with the .C, .CP, or .CPP extension. DO check your documentation for specifics about your compiler and linker to ensure that you know how to compile and link your programs.