A constant update time finger search tree

Abstract

Levcopolous and Overmars [12] describe a search tree in which the time to insert or delete a key is O(1) once the position of the key to be inserted or deleted was known. Their data structure does not support fingers, pointers to points of high access or update activity in the set such that access and update operations in the vicinity of a finger are particularly efficient [3, 8, 10, 11, 15]. Levcopolous and Overmars leave as an open question whether a data structure can be designed which allowed updates in constant time and supports fingers. We answer the question in the affirmative by giving an algorithm in the RAM with logarithmic word size model [1].