is breadth first search or breadth first traversal possible without using a queue?

Question

as i rememeber and checked, that the usual way for traversing a tree or crawling the web breadth first (BFS) is by using a queue. Is there actually a way to implement it not using a queue?

Answer 1

With recursion. But the queue is in the stack...

Answer 2

You really should be using a queue, as its easier to implement. Also, a queue allows for multiple machines to work together (one queues site while another pops sites off of the queue to traverse).

The only other way I see to do this is by using recursion (much more difficult, and uses only marginally either more or less memory).