C#使用自定义的泛型节点类实现二叉树类

// Comparer<T>.Default 属性
 
namespace _135_3
{
    public class Program
    {
        public static void Main(string[] args)
        {
            ArgumentNullException.ThrowIfNull(args);
 
            List<int> numbers = [3, 1, 4, 2];
 
            // 使用默认比较器对集合进行排序
            numbers.Sort(Comparer<int>.Default);
 
            Console.WriteLine(string.Join(", ", numbers));
        }
    }
}
//运行结果：
/*
1, 2, 3, 4
 */

public class Node<T>(T value)
{
    public T Data { get; set; } = value;
    public Node<T>? Left { get; set; } = null;
    public Node<T>? Right { get; set; } = null;
}

public class BinaryTree<T>
{
    public Node<T>? Root { get; private set; }
 
    public void AddNode(T value)
    {
        Node<T> newNode = new(value);
        if (Root == null)
        {
            Root = newNode;
        }
        else
        {
            Node<T> current = Root;
            while (true)
            {
                if (Comparer<T>.Default.Compare(value, current.Data) < 0)
                {
                    if (current.Left == null)
                    {
                        current.Left = newNode;
                        break;
                    }
                    current = current.Left;
                }
                else
                {
                    if (current.Right == null)
                    {
                        current.Right = newNode;
                        break;
                    }
                    current = current.Right;
                }
            }
        }
    }
}

BinaryTree<int> tree = new();

// 使用泛型节点类 Node<T>设计实现二叉树类
namespace _135_1
{
    public class Node<T>(T value)
    {
        public T Data { get; set; } = value;
        public Node<T>? Left { get; set; } = null;
        public Node<T>? Right { get; set; } = null;
    }
 
    public class BinaryTree<T>
    {
        public Node<T>? Root { get; private set; }
 
        public void AddNode(T value)
        {
            Node<T> newNode = new(value);
            if (Root == null)
            {
                Root = newNode;
            }
            else
            {
                Node<T> current = Root;
                while (true)
                {
                    if (Comparer<T>.Default.Compare(value, current.Data) < 0)
                    {
                        if (current.Left == null)
                        {
                            current.Left = newNode;
                            break;
                        }
                        current = current.Left;
                    }
                    else
                    {
                        if (current.Right == null)
                        {
                            current.Right = newNode;
                            break;
                        }
                        current = current.Right;
                    }
                }
            }
        }
    }
 
    class Program
    {
        static void Main(string[] args)
        {
            ArgumentNullException.ThrowIfNull(args);
 
            BinaryTree<int> tree = new();
            tree.AddNode(5);
            tree.AddNode(3);
            tree.AddNode(8);
            tree.AddNode(1);
            tree.AddNode(4);
            tree.AddNode(7);
 
            Console.WriteLine("中序遍历：");
            PrintInOrder(tree.Root!);
 
            Console.WriteLine("前序遍历：");
            PrintPreOrder(tree.Root!);
 
            Console.WriteLine("后序遍历：");
            PrintPostOrder(tree.Root!);
 
            Console.ReadKey();
        }
 
        static void PrintInOrder(Node<int> node)
        {
            if (node != null)
            {
                PrintInOrder(node.Left!);
                Console.WriteLine(node.Data);
                PrintInOrder(node.Right!);
            }
        }
 
        static void PrintPreOrder(Node<int> node)
        {
            if (node != null)
            {
                Console.WriteLine(node.Data);
                PrintPreOrder(node.Left!);
                PrintPreOrder(node.Right!);
            }
        }
 
        static void PrintPostOrder(Node<int> node)
        {
            if (node != null)
            {
                PrintPostOrder(node.Left!);
                PrintPostOrder(node.Right!);
                Console.WriteLine(node.Data);
            }
        }
    }
}