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

Example
Given: 1 –> 2 –> 6 –> 3 –> 4 –> 5 –> 6, val = 6
Return: 1 –> 2 –> 3 –> 4 –> 5

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