leetcode--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

.

/**
* 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) {
ListNode h = new ListNode(Integer.MAX_VALUE);
h.next = head;
ListNode pre = h;
ListNode cur = head;
while(cur!=null){
if(pre.val==cur.val){
pre.next = cur.next;
}else{
pre = cur;
}
cur = cur.next;
}
return head;
}
}