Book Image

C++20 STL Cookbook

By : Bill Weinman
Book Image

C++20 STL Cookbook

By: Bill Weinman

Overview of this book

Fast, efficient, and flexible, the C++ programming language has come a long way and is used in every area of the industry to solve many problems. The latest version C++20 will see programmers change the way they code as it brings a whole array of features enabling the quick deployment of applications. This book will get you up and running with using the STL in the best way possible. Beginning with new language features in C++20, this book will help you understand the language's mechanics and library features and offer insights into how they work. Unlike other books, the C++20 STL Cookbook takes an implementation-specific, problem-solution approach that will help you overcome hurdles quickly. You'll learn core STL concepts, such as containers, algorithms, utility classes, lambda expressions, iterators, and more, while working on real-world recipes. This book is a reference guide for using the C++ STL with its latest capabilities and exploring the cutting-edge features in functional programming and lambda expressions. By the end of the book C++20 book, you'll be able to leverage the latest C++ features and save time and effort while solving tasks elegantly using the STL.
Table of Contents (13 chapters)

A ToDo list using multimap

An ordered task list (or a ToDo list) is a common computing application. Formally stated, it's a list of tasks associated with a priority, sorted in reverse numerical order.

You may be tempted to use a priority_queue for this, because as the name implies, it's already sorted in priority (reverse numerical) order. The disadvantage of a priority_queue is that it has no iterators, so it's difficult to operate on it without pushing and popping items to and from the queue.

For this recipe, we'll use a multimap for the ordered list. The multimap associative container keeps items in order, and it can be accessed using reverse iterators for the proper sort order.

How to do it…

This is a short and simple recipe that initializes a multimap and prints it in reverse order.

  • We start with a type alias for our multimap:
    using todomap = multimap<int, string>;

Our todomap is a multimap with an int key and a string...