AbstractThe problem of making bounded in-degree and out-degree data structures partially persistent is considered. The node copying method of Driscoll et al. is extended so that updates can be performed in worst-case constant time on the pointer machine model. Previously it was only known to be possible in amortised constant time.
The result is presented in terms of a new strategy for Dietz and Raman's dynamic two player pebble game on graphs.
It is shown how to implement the strategy and the upper bound on the required number of pebbles is improved from 2b+2d+O(sqr(tb)) to d+2b, where b is the bound of the in-degree and d the bound of the out-degree. We also give a lower bound that shows that the number of pebbles depends on the out-degree d.
Categories and Subject Descriptors: E.1 [Data Structures]; F.2.2 [Analysis of Algorithms and Problem Complexity]: Nonnumerical Algorithms and Problems
Additional Key Words and Phrases: data structures, partial persistence, pebble game, lower bounds
Selected papers that cite this one
- Gerth Stølting Brodal. Finger search trees with constant insertion time. In Proceedings of the Ninth Annual ACM-SIAM Symposium on Discrete Algorithms, pages 540-549, San Francisco, California, 25-27 January 1998.
Selected references
- Paul F. Dietz and Rajeev Raman. Persistence, amortization and randomization. In Proceedings of the Second Annual ACM-SIAM Symposium on Discrete Algorithms, pages 78-88, San Francisco, California, 28-30 January 1991.
- James R. Driscoll, Neil Sarnak, Daniel D. Sleator, and Robert E. Tarjan. Making data structures persistent. Journal of Computer and System Sciences, 38(1):86-124, February 1989.