摘要：Emergency 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 阅读全文

摘要：Public Bike Management There is a public bike service in Hangzhou City which provides great convenience to the tourists from all over the world. One m 阅读全文

摘要：Choose the best route One day , Kiki wants to visit one of her friends. As she is liable to carsickness , she wants to arrive at her friend’s home as 阅读全文

摘要：find the safest road find the safest road XX星球有很多城市，每个城市之间有一条或多条飞行通道，但是并不是所有的路都是很安全的，每一条路有一个安全系数s,s是在 0 和 1 间的实数(包括0，1)，一条从u 到 v 的通道P 的安全度为Safe(P) = s 阅读全文