BFS using STL for competitive coding
In BFS, we start with a node. 1) Create a queue and enqueue source into it. Mark source as visited. 2) While queue is not empty, do following a) Dequeue a vertex from queue. Let this be f. b) Print f c) Enqueue all not yet visited adjacent of f and mark them visited.
Below is an example BFS starting from source vertex 1. Note that there can be multiple BFSs possible for a graph (even from a particular vertex).
For more details of BFS, refer this post .
The code here is simplified such that it could be used in competitive coding.
Input: 8 10 0 1 0 2 0 3 0 4 1 5 2 5 3 6 4 6 5 7 6 7 Output: 0 1 2 3 4 5 6 7
This article is contributed by Nikhil Mahendran. If you like GeeksforGeeks and would like to contribute, you can also write an article using write.geeksforgeeks.org or mail your article to email@example.com. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.