Re: yet another hierarchy model
From: KWillets <kwillets_at_looksmart.net>
Date: 16 Oct 2001 14:54:57 -0700
Message-ID: <eef24980.0110161354.7eb13a84_at_posting.google.com>
Date: 16 Oct 2001 14:54:57 -0700
Message-ID: <eef24980.0110161354.7eb13a84_at_posting.google.com>
Vadim Tropashko <nospam_at_newsranger.com> wrote in message news:<Urmx7.24985$ev2.33971_at_www.newsranger.com>...
> Here is one more way to represent hierarchy: just store depth-first sequence
> number and level (simple, indeed!).
>
(...until one needs to delete or insert a node.)
How about:
- Assigning unique prime numbers to all leaf nodes, and assigning
each intermediate node the product of its subordinates.
- Using a bitmap with each bit assigned to a leaf node, and or'ing the things together at intermediate nodes.
- Embedding the tree on a binary tree and keying each node by the bitstring which indicates its position in the B-tree, eg
A ---> A / | \ / \ B C D B () () is omitted / \ C D node key A 0 B 00 C 010 D 011
(Omitting the 01 node means that 01* nodes are children of 01's parent, etc.)
This kind of thing can go on and on.... Received on Tue Oct 16 2001 - 23:54:57 CEST