Yes, "tree" is not the best word, though it does hint at the existence
of branches - however its structure doesn't reveal the links. Each row
is a sorted list, I suppose. Whatever we call it, I think you've got a
big problem in finding all such "things" each with 100 unique members,
in a 2000-node graph. At least I don't yet see how to do it given the
memory problems at N=11!
Better to look at wrapc than wrapb, I suggest. It does nub after
sorting the lists as you suggest.
I'm about to do the Times Listener Crossword now (a numerical one this
week!) so won't be path hunting for a while.
Good luck
Mike
On 15/02/2013 7:19 PM, Raul Miller wrote:
Thank you, again.
I have not yet had time to read through wrapb, but a quick glance
suggests that the "too many paths (or 'trees', maybe )" issue could
probably be resolved by sorting each "path" before determining
uniqueness.
That said, I am more uncomfortable labelling these "visitable sets"
with the word "trees" rather than "paths". A tree would imply, to me,
that I've retained a particular connection structure, and all I care
about is whether the node has been visited. Perhaps I should model
this as "when a connection is used the reverse connection is also made
available in the context of that path" - actually implementing that
seems computationally inefficient, but it would resolve the conflict
between this use of the word "path" and its use in other graph
problems.
Thanks,
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