摘要：
1006 Sign In and Sign Out （25 分） At the beginning of every day, the first person who signs in the computer room will unlock the door, and the last one 阅读全文
摘要：
1005 Spell It Right （20 分） Given a non-negative integer N, your task is to compute the sum of all the digits of N, and output every digit of the sum i 阅读全文