event_date) = -1 ## Ref: https://lifewithdata.com/2021/08/03/sql-interview-questions-leetcode-550-game-play-analysis-iv/11 - 571H 给定数字的频率查询中位数 Find Median Given Frenquency of Numbers此题的一个经典解法是,找出那些不管是正序累积频数求和,还是逆序累积频数求和的数字,进行平均即可得...
SELECTSUBSTRING_INDEX( SUBSTRING_INDEX('A,B,C,D,E',',', h.help_topic_id+1),',',-1)AScharsFROMmysql.help_topicAShWHEREh.help_topic_id<( LENGTH('A,B,C,D,E')-LENGTH(REPLACE('A,B,C,D,E',',','') )+1); 上面的SQL查出来的结果如下 mysql.help_topic 是mysql中自带的一张表,...
DELETE FROM table WHERE (subquery)的写法不可用: MySQL Error 1093 - Can't specify target table for update in FROM clausestackoverflow.com/questions/45494/mysql-error-1093-cant-specify-target-table-for-update-in-from-clause In MySQL, you can't modify the same table which you use in the ...
[SQL] LeetCode 601. 体育馆的人流量 - [Hard] 601. 体育馆的人流量 题目: X city built a new stadium, each day many people visit it and the stats are saved as these columns: id, visit_date, people Please write a query to display the records which have 3 or more consecutive rows and...
I am sure that this kind of questions must have been asked before, but failed to find anything by searching this site. My apologies in advance if I missed any similar questions. Is there anything in C... Why is shared mutability bad?
LeetCode-SQL-Solutions Description The SQL 50 on LeetCode provided an extensive collection of SQL problems covering a wide range of concepts and techniques. This challenge included easy, medium and hard level questions from various topics like- Selects Basic Joins Basic Aggregate Functions Sorting an...
[LeetCode] questions conclusion_ Binary Search Binary Search T(n) = T(n/2) + O(1) => T(n) = O(lg n) proof: 如果能用iterable , 就用while loop, 可以防止用recursion的时候stack overflow( process in Linux is 8Mb), stack room is static for each process. (堆空间, heap room 是内存...
1represents thegroundcan be walked through. The place with number bigger than 1represents atreecan be walked through, and this positive number represents the tree's height. You are asked to cut off all the trees in this forest in the order of tree's height - always cut off the tree with...
LeetCode has over 1,900 questions for you to practice, covering many different programming concepts. Every coding problem has a classification of either Easy, Medium, or Hard. LeetCode problems focus on algorithms and data structures. Here is some topic you can find problems on LeetCode: Mathem...
Since free questions may be even mistakenly taken down by some companies, only solutions will be post on now. There are new LeetCode questions every week. I'll keep updating for full summary and better solutions. For more problem solutions, you can see my LintCode, GoogleKickStart, GoogleCo...