Remove all elements from a linked list of integers that have valueval.

ExampleGiven:1 --> 2 --> 6 --> 3 --> 4 --> 5 --> 6,val= 6Return:1 --> 2 --> 3 --> 4 --> 5

這道題兩個指針就可以了哇。不過我總是把指針搞混。所以我還是覺得有點繞T T

public class Solution {    public ListNode removeElements(ListNode head, int val) {        ListNode track = new ListNode(0);          track.next = head;          ListNode a = track;          ListNode b = head;          while(b!=null) {              if(b.val == val) {                  a.next = b.next;              } else {                  a = a.next;              }              b = b.next;          }                    return track.next;      }}