Remove Duplicates from Sorted List
问题:
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
.
思路:
两个指针标示
我的代码:
public class Solution { public ListNode deleteDuplicates(ListNode head) { if(head == null) return null; ListNode dummy = new ListNode(-1); ListNode pre = head; ListNode cur = head.next; dummy.next = pre; while(cur != null) { if(pre.val == cur.val) { cur = cur.next; } else { pre.next = cur; pre = cur; cur = cur.next; } } pre.next = null; return dummy.next; } }
学习之处:
链表问题,注意结尾处细节。