PAT甲级——1131 Subway Map （30 分)

最新推荐文章于 2020-04-22 10:35:06 发布

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最新推荐文章于 2020-04-22 10:35:06 发布 · 569 阅读

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#DFS

该博客讨论了PAT甲级编程竞赛中的一道题目，即如何在复杂的地铁地图上找到从起点到终点的最快路径。题目要求找出最小停靠站点数的路径，如果停靠次数相同，则选取转站次数最少的路径。博主通过DFS算法进行解决，并提到了使用visit映射避免回溯时重复访问节点，以及利用unordered_map存储线路信息以判断中转站。博客强调虽然题目逻辑复杂，但通过细心处理可以找到解题思路。

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1131 Subway Map （30 分)

In the big cities, the subway systems always look so complex to the visitors. To give you some sense, the following figure shows the map of Beijing subway. Now you are supposed to help people with your computer skills! Given the starting position of your user, your task is to find the quickest way to his/her destination.

Input Specification:

Each input file contains one test case. For each case, the first line contains a positive integer N (≤ 100), the number of subway lines. Then N lines follow, with the i-th (i=1,⋯,N) line describes the i-th subway line in the format:

M S[1] S[2] ... S[M]

where M (≤ 100) is the number of stops, and S[i]'s (i=1,⋯,M) are the indices of the stations (the indices are