Hans-Joachim Böckenhauer , Ralf Klasing , Tobias Mömke , Peter Rossmanith , Moritz Stocker , David Wehner
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引用次数: 0
Abstract
We analyze the competitive ratio of the proportional online knapsack problem with removal and limited recourse. In contrast to the classical online knapsack problem, packed items can be removed and a limited number of removed items can be re-inserted to the knapsack. The variant with removal only was analyzed by Iwama and Taketomi (ICALP, 2002). We show that even a single use of recourse can improve the performance of an algorithm. We give lower bounds for a constant number of uses of recourse in total, matching upper bounds for , and a general upper bound for any value of k. For a variant where a constant number of uses of recourse can be used per step, we give tight bounds for all . We further look at a scenario where an algorithm is informed when the instance ends and give improved upper bounds in both variants for this case.
期刊介绍:
The Journal of Computer and System Sciences publishes original research papers in computer science and related subjects in system science, with attention to the relevant mathematical theory. Applications-oriented papers may also be accepted and they are expected to contain deep analytic evaluation of the proposed solutions.
Research areas include traditional subjects such as:
• Theory of algorithms and computability
• Formal languages
• Automata theory
Contemporary subjects such as:
• Complexity theory
• Algorithmic Complexity
• Parallel & distributed computing
• Computer networks
• Neural networks
• Computational learning theory
• Database theory & practice
• Computer modeling of complex systems
• Security and Privacy.