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

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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

Their capabilities can categorize iterator. C++ has forward, bidirectional and random access iterators. With the forward iterator, you can iterate the container forward, with the bidirectional iterator, in both directions. With the random access iterator, you can directly access an arbitrary element. In particular, this means for the last one, that you can use iterator arithmetic and ordering comparisons (e.g.: `<`). The category of an iterator depends on the type of container used.

In the table below is a representation of containers and their iterator categories. The bidirectional iterator includes the forward iterator functionalities, and the random access iterator includes the forward and the bidirectional iterator functionalities. `It` and `It2` are iterators, `n` is a natural number.

The iterator categories of the container:

| **Iterator category** | **Properties** | **Container** |
|-|-|-|
| Forward iterator | `++It, It++, *It` | unordered associative container |
|                  | `It == It2, It != It2` | `std::forward_list` |
| Bidirectional iterator | `--It, It--` | ordered associative container |
|                        |              | `std::list` |
| Random access iterator | `It[i]` | `std::array` |
|                        | `It+= n, It-= n` | `std::vector` |
|                        | `It+n, It-n` | `std::deque` |
|                        | `n+It`       | `std::string` |
|                        | `It-It2`       |  |
|                        | `It < It2, It <= It2, It > It2` | |
|                        | `It >= It2` | | 
<p> <strong> The iterator categories of the container  </strong> </p>


The input iterator and the output iterator are special forward iterators: they can read and write their pointed element only once.

Iterators can be categorized into three primary types, each with its own advantages.

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