Python Program Find the Length of Linked List using Recursion

In this Python program, we will use recursion to find the length of a linked list. A linked list is a data structure consisting of nodes where each node contains data and a reference (or pointer) to the next node in the sequence.

Problem statement

Given a linked list, we need to calculate the length of the linked list using recursion.

Python Program Find the Length of Linked List using Recursion

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

class LinkedList:
    def __init__(self):
        self.head = None
    
    def append(self, data):
        new_node = Node(data)
        if not self.head:
            self.head = new_node
            return
        current = self.head
        while current.next:
            current = current.next
        current.next = new_node
    
    def length_recursive(self, node):
        if node is None:
            return 0
        return 1 + self.length_recursive(node.next)
    
    def get_length(self):
        return self.length_recursive(self.head)
llist = LinkedList()
llist.append(10)
llist.append(20)
llist.append(30)
llist.append(40)

print("Length of the linked list:", llist.get_length())

How it works

1. We define a Node class to represent individual nodes of the linked list. Each node contains data and a reference to the next node.
2. We define a LinkedList class with methods to append nodes and find the length of the linked list.
3. The length_recursive method takes a node as an argument and recursively calculates the length of the linked list starting from that node.
4. In the get_length method, we initiate the recursive length calculation from the head node of the linked list.
5. We create a linked list using the LinkedList class and append some nodes to it.
6. Finally, we call the get_length method to calculate and print the length of the linked list.

Input / Output