LeetCode Remove Duplicates from Sorted List II

题意：给出一个单链表 ，将其中重复的元素删除

思路：在找重复结点时，需要找到其前继结点

代码如下：

class Solution{    public ListNode deleteDuplicates(ListNode head)    {        ListNode cur = head, next = null, prev = null;        if (null == head) return head;        for (; cur != null; )        {            boolean found = false;            for (next = cur.next; next != null; next = next.next)            {                if (cur.val != next.val)                {                    break;                }                else found = true;            }            if (found)            {                if (null == prev)                {                    head = next;                    cur = head;                }                else                {                    prev.next = next;                    cur = next;                }            }            else            {                prev = cur;                cur = cur.next;            }        }        return head;    }}