如何在C#中删除链表中的结束值

public class ListNode
{
    public int val;
    public ListNode next;
    public ListNode(int x)
    {
        val = x;
    }
}

ListNode head = new ListNode(1);
ListNode second = new ListNode(2);
ListNode third = new ListNode(3);
ListNode fourth = new ListNode(4);

head.next = second;
second.next = third;
third.next = fourth;

int target = 4; // 结束值
ListNode dummy = new ListNode(0);
dummy.next = head;
ListNode prev = dummy;
ListNode curr = head;

while (curr != null)
{
    if (curr.val == target)
    {
        prev.next = curr.next;
    }
    else
    {
        prev = curr;
    }
    curr = curr.next;
}

head = dummy.next; // 更新链表头部

void PrintLinkedList(ListNode node)
{
    while (node != null)
    {
        Console.Write(node.val + " ");
        node = node.next;
    }
    Console.WriteLine();
}

PrintLinkedList(head);