Graphs and Combinatorics

, Volume 22, Issue 4, pp 527–543 | Cite as

Alternating Paths along Axis-Parallel Segments

Article

Abstract

It is shown that for a set S of n pairwise disjoint axis-parallel line segments in the plane there is a simple alternating path of length Open image in new window . This bound is best possible in the worst case. In the special case that the n pairwise disjoint axis-parallel line segments are protruded (that is, if the intersection point of the lines through every two nonparallel segments is not visible from both segments), there is a simple alternating path of length n.

Keywords

Alternating path Geometric graph Visibility 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  1. 1.Department of MathematicsMITCambridgeUSA

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