Book Image

C++ Fundamentals

By : Antonio Mallia, Francesco Zoffoli
Book Image

C++ Fundamentals

By: Antonio Mallia, Francesco Zoffoli

Overview of this book

C++ Fundamentals begins by introducing you to the C++ compilation model and syntax. You will then study data types, variable declaration, scope, and control flow statements. With the help of this book, you'll be able to compile fully working C++ code and understand how variables, references, and pointers can be used to manipulate the state of the program. Next, you will explore functions and classes — the features that C++ offers to organize a program — and use them to solve more complex problems. You will also understand common pitfalls and modern best practices, especially the ones that diverge from the C++98 guidelines. As you advance through the chapters, you'll study the advantages of generic programming and write your own templates to make generic algorithms that work with any type. This C++ book will guide you in fully exploiting standard containers and algorithms, understanding how to pick the appropriate one for each problem. By the end of this book, you will not only be able to write efficient code but also be equipped to improve the readability, performance, and maintainability of your programs.
Table of Contents (9 chapters)
C++ Fundamentals
Preface

Unordered Containers


Unordered associative containers differ from associative containers in that the elements have no defined order. Visually, unordered containers are often imagined as bags of elements. Because the elements are not sorted, unordered containers do not accept a comparator object to provide an order to the elements. On the other hand, all the unordered containers depend on a hash function.

he user can provide a Functor (function object) as a parameter to specify how the keys should be hashed:

Figure 5.13: Table presenting unordered containers and their descriptions

Typically, unordered containers are implemented as hash tables. The position in the array is determined using the hash function, which given a value returns the position at which it should be stored. Ideally, most of the elements will be mapped into different positions, but the hash function can potentially return the same position for different elements. This is called a collision. This problem is solved by using...