Remove Duplicates from Sorted List

Given a sorted linked list, delete all duplicates such that each element appear only once.

For example, Given 1->1->2, return 1->2. Given 1->1->2->3->3, return 1->2->3.

Solution

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode(int x) { val = x; }
 * }
 */
public class Solution {
      public ListNode deleteDuplicates(ListNode head) {
        if (head == null) return head;

        ListNode cur = head;

        while (cur != null) {
            while (cur.next != null && cur.next.val == cur.val) {
                cur.next = cur.next.next;
            }

            cur = cur.next;
        }

        return head;
    }

}