使用python实现二进制搜索树

class TreeNode:
    def __init__(self, val):
        self.val = val
        self.left = None
        self.right = None

class BinarySearchTree:
    def __init__(self):
        self.root = None

    def insert(self, val):
        if not self.root:
            self.root = TreeNode(val)
        else:
            self._insert_recursive(val, self.root)

    def _insert_recursive(self, val, node):
        if val < node.val:
            if not node.left:
                node.left = TreeNode(val)
            else:
                self._insert_recursive(val, node.left)
        else:
            if not node.right:
                node.right = TreeNode(val)
            else:
                self._insert_recursive(val, node.right)

    def search(self, val):
        return self._search_recursive(val, self.root)

    def _search_recursive(self, val, node):
        if not node or node.val == val:
            return node
        elif val < node.val:
            return self._search_recursive(val, node.left)
        else:
            return self._search_recursive(val, node.right)

# 创建一个二叉搜索树实例
bst = BinarySearchTree()

# 插入节点
bst.insert(5)
bst.insert(3)
bst.insert(7)
bst.insert(2)
bst.insert(4)
bst.insert(6)
bst.insert(8)

# 搜索节点
node = bst.search(4)
if node:
    print("节点找到：", node.val)
else:
    print("节点未找到")