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1.5D terrain guarding problem parameterized by guard range. (English) Zbl 1356.68088

Summary: The 1.5D terrain guarding problem examines a 1.5D terrain as an \(x\)-monotone polygonal chain in a plane to find the minimum guarding set for a given input terrain. This problem is NP-complete. In real world applications, guard power is limited and can only cover things within a range. Considering this limitation, the present study introduces the “terrain guard range” as a new geometric parameter by discretizing the definition of range, then presents a fixed-parameter algorithm to demonstrate that the 1.5D terrain guarding problem is fixed-parameter tractable with respect to the introduced parameter.

MSC:

68Q17 Computational difficulty of problems (lower bounds, completeness, difficulty of approximation, etc.)
68U05 Computer graphics; computational geometry (digital and algorithmic aspects)
Full Text: DOI

References:

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