说明：  问题描述 当一个用户从甲地到乙地时，由于不同需求，就有不同的交通方式及不同的交通路线。有人希望以最快速度到达，有人希望以最短距离到达，有人希望用最少的费用等。交通方式有公交车和地铁。编写一北京公交线路查询系统，通过输入起始站、终点站，为用户提供三种或以上决策的交通咨询。
(problem description When a user goes from point a to point b, there are different modes of transportation and different routes due to different demands. Some people want to arrive at the fastest speed, some people want to arrive at the shortest distance, some people want to use the least cost and so on. There are buses and subways. Compile a Beijing bus line inquiry system, provide users with three or more kinds of traffic consultation by entering the starting station and the terminal station.)