select name AS Customersfrom Customers LEFT JOIN Orders ON Customers.Id=Orders.CustomerId WHERE Orders.CustomerId IS NULL; 1. ▌答案解析 参考1:通过查询select的嵌套使用。先在Orders表中返回所有有订单的客户Id,然后在Customer查询不在Orders表中的客户Id,最后返回相应的用户名字,即为最终结果。当然,也可以...
Bonus 1: If I'm a cheater and try to check if a code is correct, I can just create a new account and submit it (because resubmit = -50 pts) instead of your way. Also, you can try to read all of the D's submissions and say all of them are cheated (joke). I submitted D t...
to be caught in 8 (he isn't dumb enough to not change the leaked code and get caught in every contest he cheated in). So of all the contests in his profile, at least half (or maybe all) of his contests are cheated. Final Message: If you are an Indian who is a fan of this g...
Even or Odd - Which is Greater? Find sum of top-left to bottom-right diagonals Find the longest gap! Find the middle element Form The Minimum Give me a Diamond Highest Rank Number in an Array How old will I be in 2099? Insert dashes Integer Difference Is n divisible by (...)? Land...
Naive Implementation Trees Union By Rank Path Compression Analysis Options More Dynamic Programming () 6.006: Dynamic Programming I: Fibonacci, ShortestPaths 6.006 Dynamic Programming II: Text Justification, Blackjack 6.006: DP III: Parenthesization Edit Distance, Knapsack 6.006: DP IV: Guitar...