2、广度优先搜索遍历图的算法：首先访问指定的起始顶点V0，从V0出发，访问V0的所有未被访问过的邻接顶点W1，W2……，Wk,然后再依次从W1，W2……，Wk出发，访问它们的所有未被访问过的邻接顶点，依次类推，直到图中所有未被访问过的邻接顶点都被访问过为止。-2, breadth-first search graph traversal algorithm: First visit to the designated start vertex V0, starting from V0, V0 visit was not visited all the vertices adjacent to W1, W2 ... ..., Wk, and then followed from the W1, W2 ... ..., Wk, the visit they all have not been visited adjacent vertex, and so on, until the map has not been visited by all adjacent vertices have been visited so far.