在从头构建的链表上用C#实现IEnumerable<T>

public class LinkedList<T> : IEnumerable<T>
{
    private class Node
    {
        public T Data { get; set; }
        public Node Next { get; set; }
    }

    private Node head;

    public void Add(T item)
    {
        Node newNode = new Node { Data = item };

        if (head == null)
        {
            head = newNode;
        }
        else
        {
            Node current = head;
            while (current.Next != null)
            {
                current = current.Next;
            }
            current.Next = newNode;
        }
    }

    public IEnumerator<T> GetEnumerator()
    {
        Node current = head;
        while (current != null)
        {
            yield return current.Data;
            current = current.Next;
        }
    }

    IEnumerator IEnumerable.GetEnumerator()
    {
        return GetEnumerator();
    }
}

LinkedList<int> list = new LinkedList<int>();
list.Add(1);
list.Add(2);
list.Add(3);

foreach (int item in list)
{
    Console.WriteLine(item);
}

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