list in c++
To create a list in C++, you can use the standard template library (STL) container called std::list
. Below are the steps to create a list in C++:
Include the necessary header file:
c++ #include <list>
Declare a list object:
c++ std::list<int> myList;
In this example, we are creating a list of integers (int
), but you can replace it with any other data type.
- Add elements to the list using the
push_back
orpush_front
functions:c++ myList.push_back(10); // Adds 10 to the end of the list myList.push_front(5); // Adds 5 to the beginning of the list
You can use either push_back
to add elements to the end of the list or push_front
to add elements to the beginning of the list.
- Access elements in the list using iterators:
c++ std::list<int>::iterator it; for (it = myList.begin(); it != myList.end(); ++it) { std::cout << *it << " "; }
Here, we declare an iterator it
and use a for
loop to iterate over the list from the beginning (myList.begin()
) to the end (myList.end()
). We use the *it
to access the value at each position.
- Remove elements from the list using the
erase
function:c++ myList.erase(myList.begin()); // Removes the first element in the list myList.erase(myList.end()); // Removes the last element in the list
The erase
function is used to remove elements from the list. In this example, we remove the first and last elements.
- Get the size of the list using the
size
function:c++ int size = myList.size();
The size
function returns the number of elements in the list, which we can then store in a variable.
This is a basic example of how to create and manipulate a list in C++. Remember to include the necessary header file, declare the list object, add elements, access elements using iterators, remove elements, and get the size of the list as needed.