Book Image

Beginning C++ Programming

By : Richard Grimes
Book Image

Beginning C++ Programming

By: Richard Grimes

Overview of this book

C++ has come a long way and is now adopted in several contexts. Its key strengths are its software infrastructure and resource-constrained applications, including desktop applications, servers, and performance-critical applications, not to forget its importance in game programming. Despite its strengths in these areas, beginners usually tend to shy away from learning the language because of its steep learning curve. The main mission of this book is to make you familiar and comfortable with C++. You will finish the book not only being able to write your own code, but more importantly, you will be able to read other projects. It is only by being able to read others' code that you will progress from a beginner to an advanced programmer. This book is the first step in that progression. The first task is to familiarize you with the structure of C++ projects so you will know how to start reading a project. Next, you will be able to identify the main structures in the language, functions, and classes, and feel confident being able to identify the execution flow through the code. You will then become aware of the facilities of the standard library and be able to determine whether you need to write a routine yourself, or use an existing routine in the standard library. Throughout the book, there is a big emphasis on memory and pointers. You will understand memory usage, allocation, and access, and be able to write code that does not leak memory. Finally, you will learn about C++ classes and get an introduction to object orientation and polymorphism.
Table of Contents (11 chapters)

Using arrays

As the name suggests, a C++ built-in array is zero or more items of data of the same type. In C++, square brackets are used to declare arrays and to access array elements:

    int squares[4]; 
for (int i = 0; i < 4; ++i)
{
squares[i] = i * i;
}

The squares variable is an array of integers. The first line allocates enough memory for four integers and then the for loop initializes the memory with the first four squares. The memory allocated by the compiler from the stack is contiguous and the items in the array are sequential, so the memory location of squares[3] is sizeof(int) following on from squares[2]. Since the array is created on the stack, the size of the array is an instruction to the compiler; this is not dynamic allocation, so the size has to be a constant.

There is a potential problem here: the size of the array is mentioned twice...