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Data structures that can store object of almost any type. (Template-based classes)
Each container has member functions. (Some are specific to the container, others are available to all containers.)
Each container has an associated header file. #include <container_type> (e.g., #include <stack>)
| Function | Description |
|---|---|
| Default constructor | Initializes an empty container |
| Overloaded constructors | Initializes containers with many options |
| Copy constructor | Initializes a container as a copy of another container |
| Move constructor | Moves existing container to new container |
| Destructor | Destroys a container |
Copy assignment (operator=) | Copy one container to another |
Move assignment (operator=) | Move one container to another |
size | Returns the number of elements in the container |
empty | Returns boolean - is the container empty? |
insert | Insert an element into the container |
operator< and operator<= | Returns boolean - compare contents of 2 containers |
operator> and operator>= | Returns boolean - compare contents of 2 containers |
operator== and operator!= | Returns boolean - are the contents of 2 containers equal or not |
swap | Swap the elements of 2 containers |
erase | Remove element(s) from a container |
clear | Remove all elements from a container |
begin and end | Returns iterators to first element or end |
rbegin and rend | Returns reverse iterators to first element or end |
cbegin and cend | Returns constant iterators to first element or end |
crbegin and crend | Returns constant reverse iterators to first element or end |
To ensure your custom objects work well with the STL, they should meet the following requirements:
A copy of the element is stored in the container.
All primitive types (e.g., int, char, double) are fine.
For non-primitive types, elements should be:
Copyable and assignable (i.e., have a copy constructor and copy assignment operator).
Movable (i.e., have a move constructor and move assignment operator) for better performance.
Ordered associative containers (e.g., std::map, std::set) require elements to be comparable:
They use operator< and operator==, so your element type must support these operators.