in that case, breadth_first_search or depth_first_search would find the path. The problem here is that we need to stop the search once we've found a connection. But neither BFS visitors nor DFS visitors seems to give us a chance to cancel the search. The discover_vertex visitor could have this ability (I slightly remember that I had the problem to cancel a search in BGL some years ago and I wasn't able to solve it by then too).
You can throw from discover_vertex visitor. Somehow I was afraid of that answer. Is an early stop such an exceptional use case that exceptions are the proper solution? Or should I consider this rather a limitation of BGL (rendering it useless for us as I will not introduce exceptions as part of the normal execution path). I wonder if this problem occurs so infrequent that
Hi, Vladimir Prus schrieb: there is no real built-in solution. Best regards Olaf Krzikalla