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题解 | #硬币兑换#

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int m...

2024-01-06

0 118

题解 | #交错序列#

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner(System.in); sc.ne...

2023-12-27

0 128

内连接即可

SELECT a.date,ROUND(have/sum,3) AS 'p' FROM (SELECT date,COUNT(*) AS 'have' FROM email WHERE type='no_completed' AND send_id NOT IN (SELECT id FROM ...

Mysql

2021-10-02

0 216

BST判定

修改了楼上题解的辅助方法check import java.util.*; class TreeNode{ int val; TreeNode left=null,right=null; TreeNode(int val){ this.val=val;} } public c...

Java

2021-09-11

0 389

牛客的课程订单分析(六)

SELECT o.id,is_group_buy,name AS 'client_name' FROM order_info o LEFT JOIN client c ON o.client_id=c.id WHERE user_id IN (SELECT user_id FROM order_...

Mysql

2021-08-29

0 282

牛客的课程订单分析(三)

击败92，代码相对简洁点 SELECT * FROM order_info WHERE user_id IN (SELECT user_id FROM order_info WHERE status='completed' AND date>'2025-10-15' AND produc...

Sqlite

2021-08-20

0 392

牛客的课程订单分析(二)

SELECT DISTINCT(t1.user_id) FROM order_info t1 JOIN (SELECT user_id ,COUNT(user_id) AS 'count' FROM order_info WHERE status='compl...

Mysql

2021-08-02

0 265