Find the Length of a Singly Linked List

Finding the Length of a Singly Linked List

Finding the length of a singly linked list involves traversing the list and counting the number of nodes. This operation is straightforward and requires iterating through the list until the end is reached.

---

Step-by-Step Process

Consider a singly linked list with the following structure:

Head -> 1 -> 2 -> 3 -> 4 -> None

To find the length of this list, follow these steps:

1. Initialize a Counter: Start with a counter set to 0.
2. Initialize a Pointer: Start with a pointer set to the head of the list.
3. Traverse the List: Move the pointer to the next node, and increment the counter each time, until the pointer reaches the end of the list (i.e., None).
4. Return the Counter: The counter now holds the length of the list.

After performing these steps, the length of the linked list will be the value of the counter.

---

Python Program to Find the Length of a Singly Linked List

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

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

    def append(self, data):
        new_node = Node(data)
        if self.head is None:
            self.head = new_node
        else:
            current = self.head
            while current.next:
                current = current.next
            current.next = new_node

    def find_length(self):
        count = 0
        current = self.head
        while current:
            count += 1
            current = current.next
        return count

    def traverse(self):
        current = self.head
        while current:
            print(current.data, end=" -> ")
            current = current.next
        print("None")

# Example usage:
linked_list = SinglyLinkedList()
linked_list.append(1)
linked_list.append(2)
linked_list.append(3)
linked_list.append(4)
print("Linked list:")
linked_list.traverse()  # Output: 1 -> 2 -> 3 -> 4 -> None
print("Length of linked list:", linked_list.find_length())  # Output: 4

This Python program defines a singly linked list with methods for appending nodes, finding the length of the list, and traversing the list. The find_length method traverses the list, counts the number of nodes, and returns the length of the list.