How to use a Linked List in C++

A linked list is a linear data structure in computer science that consists of a sequence of nodes, where each node contains a data element and a reference (or pointer) to the next node in the sequence. Unlike arrays, linked lists do not have a fixed size and can be dynamically resized during runtime. Linked lists are commonly used in computer science for implementing various data structures such as stacks, queues, and hash tables. The main advantage of linked lists is their ability to efficiently insert and delete elements from the list, as well as their flexibility in terms of size and structure. Keep reading below to learn how to use a Linked List in C++.

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How to use a Linked List in C++ with example code

A linked list is a data structure that consists of a sequence of nodes, where each node contains a value and a pointer to the next node in the sequence. Linked lists are commonly used in computer science and programming, and they can be implemented in C++ using classes and pointers.

To create a linked list in C++, we first define a class for the nodes in the list. Each node will contain a value and a pointer to the next node in the list. Here is an example of a node class:

class Node { public: int data; Node* next; };

In this example, the node class has two members: an integer value called “data” and a pointer to the next node in the list called “next”. The “next” pointer is initialized to NULL, which indicates the end of the list.

To create a linked list, we need to create instances of the node class and link them together using the “next” pointers. Here is an example of a function that creates a linked list with three nodes:

Node* createLinkedList() { Node* head = new Node(); Node* second = new Node(); Node* third = new Node();


    head->data = 1;

    head->next = second;
    second->data = 2;

    second->next = third;
    third->data = 3;

    third->next = NULL;

return head; }

In this example, we create three nodes using the “new” operator and set their “data” values. We then link the nodes together using the “next” pointers. The “head” pointer points to the first node in the list, and the “next” pointer of each node points to the next node in the list. The “next” pointer of the last node is set to NULL to indicate the end of the list.

Once we have created a linked list, we can traverse it by following the “next” pointers from one node to the next. Here is an example of a function that prints the values of each node in a linked list:

void printLinkedList(Node* head) { Node* current = head;


    while (current != NULL) {

        cout << current->data << " ";
        current = current->next;

    }

cout << endl; }

In this example, we start at the "head" of the list and follow the "next" pointers until we reach the end of the list (which is indicated by a NULL pointer). We print the "data" value of each node as we traverse the list.

Linked lists are a powerful data structure that can be used in many different applications. By using classes and pointers in C++, we can easily create and manipulate linked lists to suit our needs.

What is a Linked List in C++?

In conclusion, a linked list is a fundamental data structure in C++ that allows for efficient storage and manipulation of data. It consists of a series of nodes, each containing a value and a pointer to the next node in the list. Linked lists are particularly useful when dealing with large amounts of data that need to be dynamically allocated and deallocated. They also provide a flexible way to insert, delete, and modify elements in the list. While they may not be as efficient as arrays for certain operations, linked lists remain an essential tool for any C++ programmer's toolkit. By understanding the basics of linked lists, you can unlock a powerful tool for managing data in your programs.