摘要：
Eva loves to collect coins from all over the universe, including some other planets like Mars. One day she visited a universal shopping mall which cou 阅读全文
摘要：
One way that the police finds the head of a gang is to check people's phone calls. If there is a phone call between A and B, we say that A and B is re 阅读全文
摘要：
A Digital Library contains millions of books, stored according to their titles, authors, key words of their abstracts, publishers, and published years 阅读全文
摘要：
A family hierarchy is usually presented by a pedigree tree. Your job is to count those family members who have no child. Input Specification: Each inp 阅读全文
摘要：
As an emergency rescue team leader of a city, you are given a special map of your country. The map shows several scattered cities connected by some ro 阅读全文