删除链表中等于给定值 val 的所有元素。
示例
给定: 1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6, val = 6
返回: 1 --> 2 --> 3 --> 4 --> 5
详见：https://leetcode.com/problems/remove-linked-list-elements/description/
Java实现：
/**
* Definition for singly-linked list.
* public class ListNode {
* int val;
* ListNode next;
* ListNode(int x) { val = x; }
* }
*/
class Solution {
public ListNode removeElements(ListNode head, int val) {
if(head==null){
return null;
}
ListNode first=new ListNode(-1);
first.next=head;
ListNode cur=first;
while(cur.next!=null){
if(cur.next.val==val){
cur.next=cur.next.next;
}else{
cur=cur.next;
}
}
return first.next;
}
}