Project Scheduling with Irregular Costs: Complexity, Approximability, and Algorithms

A. Grigoriev*, G.J. Woeginger

*Corresponding author for this work

Research output: Chapter in Book/Report/Conference proceedingConference article in proceedingAcademicpeer-review


We address a generalization of the classical discrete time-cost tradeoff problem where the costs are irregular and depend on the starting and the completion times of the activities. We present a complete picture of the computational complexity and the approximability of this problem for several natural classes of precedence constraints. We prove that the problem is np-hard and hard to approximate, even in case the precedence constraints form an interval order. For orders of bounded height, there is a complexity jump: for height one, the problem is polynomially solvable, whereas for height two, it is np-hard and apx-hard. Finally, the problem is shown to be polynomially solvable for orders of bounded width and for series parallel orders.
Original languageEnglish
Title of host publication Algorithms and Computation. ISAAC 2002
EditorsP. Bose, P. Morin
PublisherSpringer, Berlin, Heidelberg
ISBN (Electronic)978-3-540-36136-7
ISBN (Print)978-3-540-00142-3
Publication statusPublished - 8 Nov 2002

Publication series

SeriesLecture Notes in Computer Science

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