摘要：
The task is really simple: given N exits on a highway which forms a simple cycle, you are supposed to tell the shortest distance between any pair of e 阅读全文
摘要：
Shuffling is a procedure used to randomize a deck of playing cards. Because standard shuffling techniques are seen as weak, and in order to avoid "ins 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