Jill likes to ride her bicycle, but since the pretty city of Greenhills where she lives has grown, Jill often uses the excellent public bus system for part of her journey.

• 试题分析 关于迷宫问题相信每一个参加信息学奥赛的选手都不会陌生。对于不同的迷宫，我们可用搜索策略或动态规划进行求解。