创建一个链表。C#

public class ListNode
{
    public int val;
    public ListNode next;

    public ListNode(int value)
    {
        val = value;
        next = null;
    }
}

public class LinkedList
{
    public ListNode head;

    public LinkedList()
    {
        head = null;
    }

    // 在链表尾部插入一个节点
    public void AddNode(int value)
    {
        ListNode newNode = new ListNode(value);

        if (head == null)
        {
            head = newNode;
        }
        else
        {
            ListNode current = head;
            while (current.next != null)
            {
                current = current.next;
            }
            current.next = newNode;
        }
    }

    // 打印链表中的所有节点值
    public void PrintList()
    {
        ListNode current = head;
        while (current != null)
        {
            Console.Write(current.val + " ");
            current = current.next;
        }
        Console.WriteLine();
    }
}

LinkedList list = new LinkedList();
list.AddNode(1);
list.AddNode(2);
list.AddNode(3);
list.PrintList();