Shortest Gently Descending Paths
نویسندگان
چکیده
A path from s to t on a polyhedral terrain is descending if the height of a point p never increases while we move p along the path from s to t. We introduce a generalization of the shortest descending path problem, called the shortest gently descending path (SGDP) problem, where a path descends, but not too steeply. The additional constraint to disallow a very steep descent makes the paths more realistic in practice. We give two approximation algorithms (more precisely, FPTASs) to solve the SGDP problem on general terrains.
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