摘要：
This time you are asked to tell the difference between the lowest grade of all the male students and the highest grade of all the female students. Inp 阅读全文
摘要：
At the beginning of every day, the first person who signs in the computer room will unlock the door, and the last one who signs out will lock the door 阅读全文
摘要：
The highest building in our city has only one elevator. A request list is made up with N positive numbers. The numbers denote at which floors the elev 阅读全文