说明：  刚好手头的项目需要为客户提供一个路线指引功能的小模块，需要自动计算图形上两点间的最短路径。工作之余想着这个算法还是比较的常用，就总结了一下，与大家共享。
(Just the project at hand to provide customers with a route guidance function module to automatically calculate the shortest path between two points on the graph. Spare time thinking of this algorithm is quite commonly used to summarize and share.)