删除链表重复节点

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

2.删除重复节点 ，去除重复节点本身

/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) {
* val = x;
* next = null;
* }
* }
*/
public class Solution {
public ListNode deleteDuplicates(ListNode head) {
if(head == null || head.next ==null)
return head;
ListNode FakeHead=new ListNode(0);
FakeHead.next=head;
ListNode pre=FakeHead;
ListNode cur=head;
while(cur!=null){
while(cur.next!=null&&cur.val==cur.next.val){
cur=cur.next;
}
if(pre.next==cur){
pre=pre.next;
}else{
pre.next=cur.next;
}
cur=cur.next;
}
return FakeHead.next;
}
}