forward_list::cend() in C++

The std::forward_list class, a component of the Standard Template Library (STL), contains the forward_list::cend() function in C++. Using this function, you can get a constant iterator that point's to the location of the next element in a forward list after the last one. The cend() function is useful for forward lists, singly linked lists, and lists that allow only forward traversal. It provide users with a constant iterator to the end of the forward list, and developers can safely loop through the container without being able to modify its elements. It is helpful if the objective is to just read or view the items in the forward list. Through the efficient and controlled traversal of a variety of STL containers, the C++ iterator-related functions—among which the cend() function is one allow programming in C++ to be more versatile and useful.

Syntax:

It has the following syntax:

forward_list_name.cend()

Parameters: The function does not take any parameter.

Return Value: The function returns an iterator pointing to the past-the-end element of the forward list container.

Methods used are:

• forward_list::cend() technique:
• It is the main approach covered in the introduction.
• It's a component of the C++ Standard Template Library (STL) and is part of the std::forward_list class.
• It gives back a constant iterator that point's to the spot in the forward list that comes right after the last element.
• Forward Listing:
• Stated to set the scene for the forward_list::cend() function.
• It is defined as a singly linked list with a forward-only traversal capability.
• Iterator Constant:
• The type of iterator that forward_list::cend() returns is highlighted.
• It is emphasized for its ability to keep elements from being altered while yet permitting reading or observation.

• Standard Template Library (STL):
• Added a bit of information on the forward_list::cend() method's context.
• It's a C++ library that offers template-based generic classes and methods for implementing a range of widely used algorithms and data structures.
• Functions linked using iterators:
• It is stated to indicate that forward_list::cend() is a member of a larger class of functions that support C++ STL's controlled traversal.
• It is implied that there are further iterator-related methods that improve the adaptability and practicality of C++ programming.

Example:

Let's take an example to illustrate the use of forward_list::cend() in C++.

#include <iostream>

#include <forward_list>

int main() {

 // Creating a forward list

 std::forward_list<int> myForwardList = {1, 22, 24, 34, 56};

 // Obtaining a constant iterator to the end of the forward list

 std::forward_list<int>::const_iterator it = myForwardList.cend();

 // Displaying the elements in the forward list using the iterator

 std::cout << "Forward List Elements: ";

 for (auto iter = myForwardList.cbegin(); iter != it; ++iter) {

 std::cout << *iter << " ";

 }

 std::cout << std::endl;

 return 0;

}

Output:

Forward List Elements: 1 22 24 34 56

Explanation:

• In this example, we initialize certain values in a std::forward_list called myForwardList.
• Using cend(), we are able to obtain a constant iterator to the end of the forward list.
• After that, the elements are iterated over and displayed using a loop that uses cbegin() and the acquired iterator.

Example 2:

Let's take another example to illustrate the use of forward_list::cend() in C++.

#include <iostream>

#include <forward_list>

int main() {

 // Creating a forward list of strings

 std::forward_list<std::string> myForwardList = {"apple", "banana", "cherry", "date"};

 // Obtaining a constant iterator to the end of the forward list

 auto endIterator = myForwardList.cend();

 // Displaying the elements in the forward list using the iterator

 std::cout << "Forward List Elements: ";

 for (auto it = myForwardList.cbegin(); it != endIterator; ++it) {

 std::cout << *it << " ";

 }

 std::cout << std::endl;

 return 0;

}

Output:

Forward List Elements: apple banana cherry date

Explanation:

• With some initial string values, we establish a std::forward_list called myForwardList.
• Using cend(), we are able to get a constant iterator to the forward list's end.
• The retrieved iterator and cbegin() are used in a loop to cycle over the string elements and demonstrate them.

Conclusion:

In C++, the function forward_list::cend() denotes a constant iterator that points to the location immediately after a forward list's final entry. In order to ensure that the iterator cannot change the underlying data, this approach is especially helpful when iterating through the members of a forward list in a read-only fashion. Const-correctness is upheld via the cend() function, which offers a way to navigate the forward list without compromising the accuracy of the data. Developers can promote proper programming behaviors and prevent unplanned alterations to the container during iteration by using forward_list::cend() to improve the safety and robustness of their code while working with forward lists.