I would like to build a visitor that accesses the colour_map of a specific vertex. The idea is to 'hide' some vertices from the search completely.
The algorithm initializes the color map to white AFTER calling
initialize_vertex. So your strategy won't work. Perhaps using filtered graph
is a better option?
If you wish to persevere with the current strategy, you could try to skip
the initialization by using the dijkstra_shortest_path_no_init function, but
be careful about also initializing the distance map and predecessor map
yourself.
Best wishes, Alex
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