Abstract
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.
This work is supported by the National Science Foundation of China (Grant No. 61173011) and a Project 985 grant of Shanghai Jiao Tong University.
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Chen, Y., Deng, X., Ji, Z., Liao, C. (2016). The Beachcombers’ Problem: Walking and Searching from an Inner Point of a Line. In: Dediu, AH., Janoušek, J., Martín-Vide, C., Truthe, B. (eds) Language and Automata Theory and Applications. LATA 2016. Lecture Notes in Computer Science(), vol 9618. Springer, Cham. https://doi.org/10.1007/978-3-319-30000-9_21
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DOI: https://doi.org/10.1007/978-3-319-30000-9_21
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