A New Approximation Algorithm for the Capacitated Vehicle Routing Problem on a Tree

  • Tetsuo Asano
  • Kazuhiro Kawashima
  • Naoki Katoh
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 1741)


This paper presents a new approximation algorithm for a vehicle routing problem on a tree-shaped network with a single depot. Customers are located on vertices of the tree. Demands of customers are served by a fleet of identical vehicles with limited capacity. It is assumed that the demand of a customer is splittable, i.e., it can be served by more than one vehicle. The problem we are concerned with in this paper asks to find a set of tours of the vehicles with minimum total lengths. Each tour begins at the depot, visits a subset of the customers and returns to the depot. We propose a 1.35078-approximation algorithm for the problem (exactly, \( (\sqrt {41} - 1)/4) \) , which is an improvement over the existing 1.5-approximation.


Approximation Algorithm Problem Instance Internal Node Approximation Ratio Capacitate Vehicle Route Problem 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1999

Authors and Affiliations

  • Tetsuo Asano
    • 1
  • Kazuhiro Kawashima
    • 1
  • Naoki Katoh
    • 2
  1. 1.JAISTSchool of Information ScienceAsahidaiJapan
  2. 2.Department of Architecture and Architectural SystemsKyoto UniversitySakyo-kuJapan

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