Java – Measuring Up `size()`- Doubly Linked List

Hey Dev.to folks!

Want to know how many nodes are in your doubly linked list? Look no further: here comes the size() method.

Quick Doubly Linked List Recap:

Here’s our foundational setup:

class Node {
    int data;
    Node next;
    Node prev;

    // Constructor to initialize the node
    Node(int data) {
        this.data = data;
        this.next = null;
        this.prev = null;
    }
}

class DoublyLinkedList {
    Node head;
    Node tail;

    // Constructor to initialize the doubly linked list
    DoublyLinkedList() {
        this.head = null;
        this.tail = null;
    }
}

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Remember, in a doubly linked list, each node knows about its next and previous node.

🧮 Breaking Down size():

Let’s get counting:

public int size() {
    int count = 0;          // Initialize the counter to zero
    Node current = head;    // Start at the beginning of the list

    while (current != null) {
        count++;            // Increase the counter for each node
        current = current.next; // Move to the next node in the list
    }

    return count;           // Return the total number of nodes
}

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The gist is simple: start at the head, traverse the list, and count each node until you reach the end.

Why size() Matters:

Knowing the size of your list can be essential, especially when you’re adding, removing, or accessing elements.

In Conclusion:

The size() method is a basic but essential tool for managing a doubly linked list.

In the next article we will look at isEmpty() method

Cheers and happy coding!

原文链接：Java – Measuring Up `size()`- Doubly Linked List