Maintaining dictionaries: Space-saving modifications of B-trees
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It is known that the data structure of B-trees leads to an exhaustive waste of memory, when lengths of keys differ very much from each other. This effect may be fixed with appropriate modifications of (he data structure. We introduce a variant of B-trees, called B-trees with unfixed key length, and compare it to another variant of B-trees, introduced by T.H. Martin, which we call B-trees with bounded key length. Space efficiency of those two variants is evaluated for the worst case. However, the efficiency for the more realistic average case remains unknown. We believe that in many applications B-trees with unfixed key length are more efficient.
KeywordsWeight Function Hash Function Linear Order Internal Vertex Direct Descendant
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