Create DoublyLInkedLIst_Implementation.java

doubly_linked_list/DoublyLInkedLIst_Implementation.java

@@ -0,0 +1,109 @@
+class Node<T> {
+    T data;
+    Node<T> next;
+    Node<T> prev;
+
+    public Node(T data) {
+        this.data = data;
+        this.next = null;
+        this.prev = null;
+    }
+}
+
+class DoublyLinkedList<T> {
+    private Node<T> head;
+    private Node<T> tail;
+    private int size;
+
+    public DoublyLinkedList() {
+        head = null;
+        tail = null;
+        size = 0;
+    }
+
+    public boolean isEmpty() {
+        return size == 0;
+    }
+
+    public int size() {
+        return size;
+    }
+
+    public void addFirst(T data) {
+        Node<T> newNode = new Node<>(data);
+        if (isEmpty()) {
+            head = newNode;
+            tail = newNode;
+        } else {
+            newNode.next = head;
+            head.prev = newNode;
+            head = newNode;
+        }
+        size++;
+    }
+
+    public void addLast(T data) {
+        Node<T> newNode = new Node<>(data);
+        if (isEmpty()) {
+            head = newNode;
+            tail = newNode;
+        } else {
+            newNode.prev = tail;
+            tail.next = newNode;
+            tail = newNode;
+        }
+        size++;
+    }
+
+    public void removeFirst() {
+        if (!isEmpty()) {
+            head = head.next;
+            if (head != null) {
+                head.prev = null;
+            } else {
+                tail = null;
+            }
+            size--;
+        }
+    }
+
+    public void removeLast() {
+        if (!isEmpty()) {
+            tail = tail.prev;
+            if (tail != null) {
+                tail.next = null;
+            } else {
+                head = null;
+            }
+            size--;
+        }
+    }
+
+    public void display() {
+        Node<T> current = head;
+        while (current != null) {
+            System.out.print(current.data + " ");
+            current = current.next;
+        }
+        System.out.println();
+    }
+}
+
+public class DoublyLInkedLIst_Implementation {
+    public static void main(String[] args) {
+        DoublyLinkedList<Integer> dll = new DoublyLinkedList<>();
+        dll.addFirst(1);
+        dll.addLast(2);
+        dll.addLast(3);
+        dll.addFirst(0);
+
+        System.out.println("Doubly Linked List:");
+        dll.display(); // Output: 0 1 2 3
+
+        dll.removeFirst();
+        dll.removeLast();
+
+        System.out.println("Doubly Linked List after removal:");
+        dll.display(); // Output: 1 2
+    }
+}