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题解 | #链表的奇偶重排#

import java.util.*; /* * public class ListNode { * int val; * ListNode next = null; * public ListNode(int val) { * this.val = val; * ...

2023-06-19

0 287

题解 | #删除有序链表中重复的元素-II#

import java.util.*; /* * public class ListNode { * int val; * ListNode next = null; * public ListNode(int val) { * this.val = val; * ...

2023-06-18

1 199

题解 | #删除有序链表中重复的元素-I#

import java.util.*; /* * public class ListNode { * int val; * ListNode next = null; * public ListNode(int val) { * this.val = val; * ...

2023-06-18

1 177

题解 | #近三个月未完成试卷数为0的用户完成情况#

select uid,cntSum as exam_complete_cnt from ( select uid, sum(case when rankNum >=1 then 1 else 0 end) rankSum, sum(case when cnt >= 1 then 1 el...

2023-06-11

0 257

题解 | #每类试卷得分前3名#

select * from ( select ei.tag, er.uid, rank() over(partition by ei.tag order by max(er.score) desc,min(er.score) desc,er.uid desc ) ranking from exa...

2023-06-07

0 199

题解 | #分组计算练习题#

select gender,university, count(device_id) user_num, round(sum(active_days_within_30)/count(device_id),1) avg_active_day, round(sum(question_cnt)/c...

2023-06-06

0 217

题解 | #统计复旦用户8月练题情况#

select u.device_id, u.university, sum(case when result is not null then 1 else 0 end) as question_cnt, sum(case when result = 'right' then 1 else 0 ...

2023-06-05

0 179

题解 | #21年8月份练题总数#

select count(distinct(device_id)) did_cnt, count(result) question_cnt from question_practice_detail where month(`date`) = '08' group by month (`date`...

2023-06-05

0 183

题解 | #找出每个学校GPA最低的同学#

select device_id,university,gpa from (select device_id,university,gpa,row_number () over(partition by university order by gpa asc) rankNum from (sele...

2023-06-03

0 254

题解 | #注册当天就完成了试卷的名单第三页#

-- 1.选取考算法的作答记录 with t as(SELECT er.uid,er.exam_id,er.start_time,er.submit_time,er.score,ei.tag from exam_record er join examination_info ei ON er.exa...

Mysql

2022-09-03

0 227