An Improved Approximation Algorithm for the Coupled-Task Scheduling Problem with Equal Exact Delays

  • Alexander AgeevEmail author
  • Mikhail Ivanov
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 12095)


We study the coupled-task single machine scheduling problem with equal exact delays and makespan as the objective function. It is known that the problem cannot be approximated with a factor better than 1.25 unless P \(=\) NP. In this paper, we present a 2.5-approximation algorithm for this problem, which improves the best previously known approximation bound of 3. The algorithm runs in time \(O(n\log n)\) where n is the number of jobs.


Coupled-task scheduling Inapproximability lower bound Approximation algorithm Worst-case analysis 



The authors thank the anonymous referees for their helpful comments and suggestions.


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© Springer Nature Switzerland AG 2020

Authors and Affiliations

  1. 1.Sobolev Institute of MathematicsNovosibirskRussia
  2. 2.Novosibirsk State UniversityNovosibirskRussia

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