Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
For example,
Given 1->2->3->3->4->4->5
, return 1->2->5
.
Given 1->1->1->2->3
, return 2->3
.
public ListNode deleteDuplicates(ListNode head) { ListNode dummy = new ListNode(0); ListNode node = dummy; while(head != null) { ListNode p = head; while(head.next != null && head.val == head.next.val) { head = head.next; } if(p == head) { node = node.next = p; } head = head.next; } node.next = null; return dummy.next; }