摘要:
http://poj.org/problem?id=1751 Description The island nation of Flatopia is perfectly flat. Unfortunately, Flatopia has a very poor system of public h 阅读全文
摘要:
http://poj.org/problem?id=2349 Description The Department of National Defence (DND) wishes to connect several northern outposts by a wireless network. 阅读全文