Illuminating labyrinths
A labyrinth is set L  of line segments in the plane (E2) ( E 2 ) such that the line segments have pairwise disjoint relative interiors and their complement E2\?L E 2 \ ? L is connected. This paper gives combinatorial bounds on four classical illumination problems for labyrinths. For comparison, we refer to bounds on the corresponding problems in the presence of disjoint opaque line segments.
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