Introduction to Algorithms: graph traversal ---- depth-first search (DFS) and breadth-first search (BFS)
Graph traversal
1. FIG defined
Simply put, by a few small dots in FIG. (Called vertices) and the straight lines connecting these dots (called side) thereof.
Figure 2. Classification
FIG undirected graphs can be divided and digraph
- Undirected graph
- Directed graph
3. graph traversal algorithm
1. depth-first search (DFS)
Graph traversal DFS thought
First, a vertex is not visited as the starting vertex, go unvisited vertex along the edge of the current vertex; when there is no unvisited vertex, then back to a vertex, continue to test access to other vertices until all vertices have been visited. clearly, a depth-first traversal along a branch graph traversal until the end, and then back again the same manner traversing along one another, until all vertices have been visited so far.
Legend Profile
In the above example undirected graph, the search path for the FIG DFS:
DFS route search is: 1-> 2-> 4-> 3-> 5
Code address
Undirected graph traversal DFS- Graphs and FIG.
2. The breadth-first search (BFS)
BFS graph traversal thought
First, a vertex not been accessed as a start vertex, access to all of its adjacent vertices, then each adjacent vertex, vertex and then access their adjacent not been accessed until all vertices have been visited too, traverse end.
Legend Profile
In the above example undirected graph, the search path for the next BFS in FIG:
route BFS search is: 1-> 2-> 3-> 5-> 4