Excel can sort records according to any column. Now you are supposed to imitate this function.

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 exits.

Zhejiang University has 40,000 students and provides 2,500 courses. Now given the registered course list of each student, you are supposed to output the student...

With highways available, driving a car from Hangzhou to any other city is easy. But since the tank capacity of a car is limited, we have to find gas stations on...

Zhejiang University has 40000 students and provides 2500 courses. Now given the student name lists of all the courses, you are supposed to output the registered...

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 roads. Amoun...

先来简单说一下list的contains方法的作用，它的目的就是查看给定元素是否在list中存在，所以经常用于去除重复记录。用下面一个例子来说明一下。 从数据库中查询出满足一系列条件的记录，然后以对象的形式封装到List中去。...

很多时候需要手机号进行注册，并且需要对手机号码归属于那个运营商做一下判断。先来说一下思路：首先，需要获取到用户输入的手机号码，然后将目前三大运营商运营的手机号码前缀分别组成list数组，然后截取用户手机号码前缀，看归...

前前后后分析了三遍这个双端队列，但是一直没有去写一篇文章，中途有些事情给耽搁了，所以这次就来输出了，这是自己关于分析集合类的第13篇源码分析的文章，继续分析吧。...

There are N robots standing on the ground (Don't know why. Don't know how).