Summary: In Proc. 32nd IEEE Sympos. Foundations of
ComputerScience,879 642­­649, 1991.
Faster Uniquely Represented Dictionaries
Arne Andersson Thomas Ottmann
Department of Computer Science Institut f¨ur Informatik
Lund University Universit¨at Freiburg
S­221 00 Lund, Sweden Rheinstr. 10--12, W­7800 Freiburg, Germany
email: Arne.Andersson@dna.lth.se email: ottmann@informatik.uni­freiburg.de
Abstract
We present a solution to the dictionary problem
where each subset of size n of an ordered universe
is represented by a unique structure, containing a
(unique) binary search tree. The structure permits
the execution of search, insert and delete operations
in O(n 1=3 ) time in the worst case. We also give a
general lower bound, stating that for any unique rep­
resentation of a set in a graph of bounded outdegree,
one of the operations search or update must require a
cost of \Omega\Gamma n 1=3 ). Therefore, our result sheds new light
on previously claimed lower bounds for unique binary

Source: Andersson, Arne - Department of Information Technology, Uppsala Universitet

Collections: Computer Technologies and Information Sciences