public Node merge(Node head) {
if (head == null || head.next == null) {
return head;
}
Node newHead = merge(head.next);
if (head.val == newHead.val) {
head.counter = head.counter + newHead.counter;
head.next = newHead.next;
}
return head;
}
public static void main(String[] args) {
ListNodeWithCounter test = new ListNodeWithCounter();
Node head = new Node(1, 1);
head.next = new Node(1, 3);
head.next.next = new Node(4, 2);
head.next.next.next = new Node(3, 1);
head.next.next.next.next = new Node(3, 1);
Node node = test.merge(head);
while (node != null) {
System.out.print(node.val + ", " + node.counter + "->");
node = node.next;
}
}