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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: Standard Set types don't support a feature
Date: Sun, 29 Oct 2017 19:27:50 +0100
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Date: 2017-10-29T19:27:50+01:00
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On 2017-10-29 18:35, Victor Porton wrote:

> If I first calculate transitive closure and store it in a matrix (or as I
> consider, a sparse matrix represented as a set of pairs), then checking
> existence of path between two given elements becomes much faster.

Yes, an ordered set of node pairs with a hash or else binary search to 
look for a pair.

> Well, maybe all it is a preliminary optimization. Maybe regular (non-sparse)
> incidence matrix will be not slower.

Rather faster, considering 2D Boolean array.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de