Explore the full potential of C++ by mastering the standard library.

Become a C++ Programmer

The C++ standard library is a collection of all the tools and utilities available in C++. It received its latest update in 2017, known as C++17. The update introduces many new features that further optimize our code. This module will help us fully grasp C++ and use it to its full potential.

C++ Standard Library


[`std::map`](http://en.cppreference.com/w/cpp/container/map) is by far the most frequently used associative container. The reason is simple; It combines adequate [performance](https://www.educative.io/courses/cpp-fundamentals-for-professionals/performance) with a very convenient interface. We can access its elements via the index operator. If the key doesn't exist, `std:map` creates a key-value pair. For the value, the default constructor is used.

><span>🔑</span> **Consider `std::map` as a generalization of `std::vector`**
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Often, `std::map` is called an associative array because `std::map` supports the index operator like a sequential container. The subtle difference is that its index is not restricted to a number like in the case of `std::vector`. Its index can be almost any arbitrary type.
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>The same observations hold for its namesake `std::unordered_map`.

In addition to the index operator, `std::map` supports the `at` method.The compiler checks the `at` function to make sure it is not out of bounds. So if the request key doesn't exist in the `std::map`, an `std::out_of_range` exception is thrown.

Now, we shall look at the features of std::map which make it such a popular container.

Maps