航线选择问题

问题描述

某个国家有 N 个城市，分别编号为 1 到 N。旅行者通过该国的机场售票处了解到 N

个城市之间的所有航班，每个航班都有两个属性，航程和费用，航线是双向的。

旅行者的出发点是城市 1 ，他的目的地是城市 N ，由于飞机票的价格不菲，而旅行

者携带的现金又是十分有限，而他希望使用有限的现金，尽快到达目的地。

编程任务

帮助旅行者计算出，在他所携带现金的范围内，从出发点到目的地的最短距离-Route choice problems described a country N cities, respectively, numbered from 1 to N. Ticket office learned that all flights between the N cities traveled through the country' s airports, each flight has two attributes, range and cost, the route is two-way. Traveler' s point of departure city, destination city N air tickets are expensive, and travelers carrying cash is very limited, and he hopes to use the limited cash to reach their destination as soon as possible. The programming task Traveller calculated, the shortest distance from the departure point to the destination, in the range of his carrying cash