Table: Followers
\n+-------------+------+\n| Column Name | Type |\n+-------------+------+\n| user_id | int |\n| follower_id | int |\n+-------------+------+\n(user_id, follower_id) is the primary key (combination of columns with unique values) for this table.\nThis table contains the IDs of a user and a follower in a social media app where the follower follows the user.\n\n
\n\n
Write a solution that will, for each user, return the number of followers.
\n\nReturn the result table ordered by user_id in ascending order.
The result format is in the following example.
\n\n\n
Example 1:
\n\n\nInput: \nFollowers table:\n+---------+-------------+\n| user_id | follower_id |\n+---------+-------------+\n| 0 | 1 |\n| 1 | 0 |\n| 2 | 0 |\n| 2 | 1 |\n+---------+-------------+\nOutput: \n+---------+----------------+\n| user_id | followers_count|\n+---------+----------------+\n| 0 | 1 |\n| 1 | 1 |\n| 2 | 2 |\n+---------+----------------+\nExplanation: \nThe followers of 0 are {1}\nThe followers of 1 are {0}\nThe followers of 2 are {0,1}\n\n",
"translatedTitle": "求关注者的数量",
"translatedContent": "表： Followers
\n+-------------+------+\n| Column Name | Type |\n+-------------+------+\n| user_id | int |\n| follower_id | int |\n+-------------+------+\n(user_id, follower_id) 是这个表的主键（具有唯一值的列的组合）。\n该表包含一个关注关系中关注者和用户的编号，其中关注者关注用户。\n\n
\n\n
编写解决方案，对于每一个用户，返回该用户的关注者数量。
\n\n按 user_id 的顺序返回结果表。
查询结果的格式如下示例所示。
\n\n\n\n
示例 1：
\n\n\n输入：\nFollowers 表：\n+---------+-------------+\n| user_id | follower_id |\n+---------+-------------+\n| 0 | 1 |\n| 1 | 0 |\n| 2 | 0 |\n| 2 | 1 |\n+---------+-------------+\n输出：\n+---------+----------------+\n| user_id | followers_count|\n+---------+----------------+\n| 0 | 1 |\n| 1 | 1 |\n| 2 | 2 |\n+---------+----------------+\n解释：\n0 的关注者有 {1}\n1 的关注者有 {0}\n2 的关注者有 {0,1}\n",
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