The Beachcombers’ Problem: Walking and Searching from an Inner Point of a Line

  • Yu Chen
  • Xiaotie Deng
  • Ziwei JiEmail author
  • Chao Liao
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9618)


We consider n beachcombers who are set to search a line segment whose length can be any real number. Each beachcomber has a high walking speed and a lower searching speed of its own. The problem is to find the optimal schedule such that the line segment can be searched with the minimum makespan.

We assume that the length of the segment is known in advance and beachcombers all start from an arbitrary inner point of the line segment. We show that the problem is NP-hard even if all beachcombers have the same walking speed. Then we give an efficient algorithm for the case where all beachcombers are identical.


Computational complexity Mobile agents Algorithms Schedule Searching Walking Speed Partitioning 


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© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Zhiyuan CollegeShanghai Jiao Tong UniversityShanghaiPeople’s Republic of China
  2. 2.Department of Computer ScienceShanghai Jiao Tong UniversityShanghaiPeople’s Republic of China

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