{ "data": { "question": { "questionId": "608", "questionFrontendId": "608", "categoryTitle": "Database", "boundTopicId": 2637, "title": "Tree Node", "titleSlug": "tree-node", "content": "

Table: Tree

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\n+-------------+------+\n| Column Name | Type |\n+-------------+------+\n| id          | int  |\n| p_id        | int  |\n+-------------+------+\nid is the column with unique values for this table.\nEach row of this table contains information about the id of a node and the id of its parent node in a tree.\nThe given structure is always a valid tree.\n
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Each node in the tree can be one of three types:

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Write a solution to report the type of each node in the tree.

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Return the result table in any order.

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The result format is in the following example.

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Example 1:

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\nInput: \nTree table:\n+----+------+\n| id | p_id |\n+----+------+\n| 1  | null |\n| 2  | 1    |\n| 3  | 1    |\n| 4  | 2    |\n| 5  | 2    |\n+----+------+\nOutput: \n+----+-------+\n| id | type  |\n+----+-------+\n| 1  | Root  |\n| 2  | Inner |\n| 3  | Leaf  |\n| 4  | Leaf  |\n| 5  | Leaf  |\n+----+-------+\nExplanation: \nNode 1 is the root node because its parent node is null and it has child nodes 2 and 3.\nNode 2 is an inner node because it has parent node 1 and child node 4 and 5.\nNodes 3, 4, and 5 are leaf nodes because they have parent nodes and they do not have child nodes.\n
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Example 2:

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\nInput: \nTree table:\n+----+------+\n| id | p_id |\n+----+------+\n| 1  | null |\n+----+------+\nOutput: \n+----+-------+\n| id | type  |\n+----+-------+\n| 1  | Root  |\n+----+-------+\nExplanation: If there is only one node on the tree, you only need to output its root attributes.\n
\n", "translatedTitle": "树节点", "translatedContent": "

表：Tree

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\n+-------------+------+\n| Column Name | Type |\n+-------------+------+\n| id          | int  |\n| p_id        | int  |\n+-------------+------+\nid 是该表中具有唯一值的列。\n该表的每行包含树中节点的 id 及其父节点的 id 信息。\n给定的结构总是一个有效的树。\n
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树中的每个节点可以是以下三种类型之一：

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编写一个解决方案来报告树中每个节点的类型。

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以 任意顺序 返回结果表。

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结果格式如下所示。

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示例 1：

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\n输入：\nTree table:\n+----+------+\n| id | p_id |\n+----+------+\n| 1  | null |\n| 2  | 1    |\n| 3  | 1    |\n| 4  | 2    |\n| 5  | 2    |\n+----+------+\n输出：\n+----+-------+\n| id | type  |\n+----+-------+\n| 1  | Root  |\n| 2  | Inner |\n| 3  | Leaf  |\n| 4  | Leaf  |\n| 5  | Leaf  |\n+----+-------+\n解释：\n节点 1 是根节点，因为它的父节点为空，并且它有子节点 2 和 3。\n节点 2 是一个内部节点，因为它有父节点 1 和子节点 4 和 5。\n节点 3、4 和 5 是叶子节点，因为它们有父节点而没有子节点。\n
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示例 2：

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\n输入：\nTree table:\n+----+------+\n| id | p_id |\n+----+------+\n| 1  | null |\n+----+------+\n输出：\n+----+-------+\n| id | type  |\n+----+-------+\n| 1  | Root  |\n+----+-------+\n解释：如果树中只有一个节点，则只需要输出其根属性。\n
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\\u7248\\u672c\\uff1aMySQL 8.0<\\/code><\\/p>\"],\"mssql\":[\"MS SQL Server\",\"

mssql server 2019.<\\/p>\"],\"oraclesql\":[\"Oracle\",\"

Oracle Sql 11.2.<\\/p>\"],\"pythondata\":[\"Pandas\",\"

Python 3.10 with Pandas 2.0.2 and NumPy 1.25.0<\\/p>\"],\"postgresql\":[\"PostgreSQL\",\"

PostgreSQL 16<\\/p>\"]}", "book": null, "isSubscribed": false, "isDailyQuestion": false, "dailyRecordStatus": null, "editorType": "CKEDITOR", "ugcQuestionId": null, "style": "LEETCODE", "exampleTestcases": "{\"headers\":{\"Tree\":[\"id\",\"p_id\"]},\"rows\":{\"Tree\":[[1,null],[2,1],[3,1],[4,2],[5,2]]}}\n{\"headers\":{\"Tree\":[\"id\",\"p_id\"]},\"rows\":{\"Tree\":[[1,null]]}}", "__typename": "QuestionNode" } } }