// try this
public ListNode removeDuplicateElements(ListNode head) {
if (head == null || head.next == null) {
return null;
}
if (head.data.equals(head.next.data)) {
ListNode next_next = head.next.next;
head.next = null;
head.next = next_next;
removeDuplicateElements(head);
} else {
removeDuplicateElements(head.next);
}
return head;
}
solved Delete duplicate element from sorted linkedlist using recursion in java [closed]