算法速刷（LeetCode）（203. 移除链表元素）

代码如下：

/**
 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
 */
class Solution {
    public ListNode removeElements(ListNode head, int val) {
        
        if(head == null) {
            return null;
        }
        ListNode dummy = new ListNode(-1,head);
        ListNode p = dummy;
        while(p.next != null) {
            if(p.next.val == val) {
                p.next = p.next.next;
            }else {
                p = p.next;
            }
        }
        return dummy.next;
    }
}