Create a Simple Linked List Using Python

Step 1: Create a Node Class

Every linked list has nodes that are linked together to form a linked list. A node contains a data and a link. The link is used to store the address of the next element in the list.

Let's create a Node class in python:

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

Step 2: Create a Linked List Class

A linked list class will contain the head of the linked lists and other methods like insert, delete and search.

Let's create a LinkedList class in python:

class LinkedList:
    def __init__(self):
        self.head = None

Step 3: Create a Linked List

In order to create a linked list, we need to create an object from the LinkedList class.

LL = LinkedList()

Now let's create 3 nodes with values 10, 11 and 12. The first node is the head.

LL.head = Node(10)
second = Node(11)
third = Node(12)

Link all the nodes together: head will point to second and second will point to third. The third node points to None which is already set.

LL.head.next = second
second.next = third

Step 4: Create a Method to Print the list

Let's add a printList() method to the LinkedList class. This method will take the head node and print the values while traversing the node until it reaches the end.

class LinkedList:
    def __init__(self):
        self.head = None

    def printList(self):
        temp = self.head
        while temp:
            print(temp.data)
            temp = temp.next

We have to call the printList() method in order to print the linked list.

LL.printList()

This is how the output will look:

10
11
12

The complete python program:

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

class LinkedList:
    def __init__(self):
        self.head = None

    def printList(self):
        temp = self.head
        while temp:
            print(temp.data)
            temp = temp.next


LL = LinkedList()

LL.head = Node(1)
second = Node(2)
third = Node(3)

LL.head.next = second
second.next = third

LL.printList()

Thanks for reading the post 😄

References:

1. https://www.geeksforgeeks.org/linked-list-set-1-introduction/