Data Structures and Algorithms: Length of Linked List 🎯

Welcome to our deep dive into the fascinating world of Data Structures and Algorithms! Today, we'll focus on a crucial problem - determining the length of a Linked List 📝. This lesson is designed to help both beginners and intermediates understand the concept from the ground up. Let's get started!

What is a Linked List? 💡

A Linked List is a linear data structure, consisting of nodes that contain data and a reference (link) to the next node in the sequence. This structure is dynamic, allowing for efficient insertion and deletion of elements.

markdown

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

In the above code, we define a basic Node class. Each node has a data attribute (the actual value) and a next attribute (a reference to the next node).

Creating a Linked List 📝

Let's create a simple Linked List with some data.

markdown

head = Node(1)
second = Node(2)
head.next = second

In this example, we create a Linked List with two nodes: 1 and 2. We connect the second node to the first one using the next attribute.

Finding the Length of a Linked List 💡

To find the length of a Linked List, we traverse the list from the head node, counting each node we encounter.

markdown

def length(head):
    current = head
    count = 0
    while current is not None:
        count += 1
        current = current.next
    return count

In the above code, we define a function length(head) that calculates the length of a given Linked List. We start from the head node, iteratively moving to the next node, incrementing the count for each node we visit.

Putting it all together 💡

Let's create a Linked List and calculate its length.

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

print(length(head))  # Output: 3

In this example, we create a Linked List with three nodes (1, 2, and 3) and calculate its length, which is 3.

Quiz Time 🎯

By the end of this lesson, you should have a solid understanding of how to create and traverse a Linked List, as well as determining its length. Happy coding! 🚀