Retroactive data structures

We introduce a new data structuring paradigm in which operations can be performed on a data structure not only in the present but also in the past. In this new paradigm, called retroactive data structures, the historical sequence of operations performed on the data structure is not fixed. The data structure allows arbitrary insertion and deletion of operations at arbitrary times, subject only to consistency requirements. We initiate the study of retroactive data structures by formally defining the model and its variants. We prove that, unlike persistence, efficient retroactivity is not always achievable. Thus, we present efficient retroactive data structures for queues, doubly ended queues, priority queues, union-find, and decomposable search structures. Categories and Subject Descriptors: E.1 [Data]: Data Structures; F.2.2 [Analysis of Algorithms and Problem Complexity]: Nonnumerical Algorithms and Problems General Terms: Algorithms, Theory, Design, Performance Additional Key Words an...

• Type: Conference
• Year: 2004
• Where: SODA
• Authors: Erik D. Demaine, John Iacono, Stefan Langerman
• Keywords: Algorithms, Data Structures, Data Structuring Paradigm, Retroactive Data Structures, SODA 2004