Building Linked List Data Structures in Python

What is Linked List?

A linked list is a linear data structure where each element, called a node, contains a reference to an object and a reference to the next node in the list. This structure allows for efficient insertion and removal of elements, as the references only need to be updated, rather than all elements being shifted in memory. Linked lists can be singly-linked, where each node only points to the next node, or doubly-linked, where each node points to both the next and previous nodes.

Linked lists are often used as an alternative to arrays when the size of the data is unknown or changing frequently, as elements can be easily added or removed without the need to allocate new memory or move existing elements. Linked lists can also be used to implement various abstract data structures such as stacks, queues, and associative arrays.

Creating a Linked List

Each node in a linked list consists of two parts: the data and a reference to the next node in the list. To create a linked list, we first define a class for the nodes, called "Node", that has two properties: "data" and "next". The "data" property holds the element's value, while the "next" property holds the reference to the next node. Here's an example in Python:

class Node:
    def __init__(self, data):
        self.data = data
        self.next = None

Next, we create the linked list itself, which consists of a head node that references the first node in the list, and a tail node that references the last node.