##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
##### ###### ##### ### # # ### # # ###### ## ## ## ## ## ## ## # # # # # ## ##### #### ##### # # # # # # # #### ## # ## ## ## ## # # # # # ## ## # ###### ## ### # ### # ######
Example trace
Example tree: edges (,), (,), (,), (,).
First BFS from node : distances are {:, :, :, :, :}. Farthest nodes are and (distance ). Pick .
Second BFS from node : distances are {:, :, :, :, :}. Farthest node is (distance ). The diameter is : the path ---.
Notice how starting from an arbitrary node () found an endpoint (), and BFS from there found the true diameter.
