c#二叉树如何转换为双向链表

要将二叉树转换为双向链表，可以使用中序遍历来实现。具体步骤如下：

1. 创建一个类来表示双向链表的节点，包括指向前一个节点和后一个节点的指针。

public class Node {     public int val;     public Node prev;     public Node next;      public Node(int val)     {         this.val = val;         this.prev = null;         this.next = null;     } } 

2. 创建一个类来表示二叉树的节点，包括左子节点和右子节点。

public class TreeNode {     public int val;     public TreeNode left;     public TreeNode right;      public TreeNode(int val)     {         this.val = val;         this.left = null;         this.right = null;     } } 

3. 编写一个递归函数来实现中序遍历，并在遍历过程中将二叉树转换为双向链表。

public class Solution {     private Node prev;      public Node Convert(TreeNode root)     {         if (root == null)             return null;          Node dummy = new Node(-1);         prev = dummy;          InOrder(root);          Node head = dummy.next;         head.prev = null;          return head;     }      private void InOrder(TreeNode node)     {         if (node == null)             return;          InOrder(node.left);          Node current = new Node(node.val);         prev.next = current;         current.prev = prev;         prev = current;          InOrder(node.right);     } } 

4. 在主函数中调用Convert方法，将二叉树转换为双向链表。

class Program {     static void Main(string[] args)     {         TreeNode root = new TreeNode(4);         root.left = new TreeNode(2);         root.right = new TreeNode(5);         root.left.left = new TreeNode(1);         root.left.right = new TreeNode(3);          Solution solution = new Solution();         Node head = solution.Convert(root);          // 遍历双向链表         Node currentNode = head;         while (currentNode != null)         {             Console.Write(currentNode.val + " ");             currentNode = currentNode.next;         }     } } 

运行上面的代码，即可将二叉树转换为双向链表，并输出双向链表的值。