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Title: Improved approximation bounds for the minimum constraint removal problem
In the minimum constraint removal problem, we are given a set of overlapping geometric objects as obstacles in the plane, and we want to find the minimum number of obstacles that must be removed to reach a target point t from the source point s by an obstacle-free path. The problem is known to be intractable and no sub-linear approximations are known even for simple obstacles such as rectangles and disks. The main result of our paper is an approximation framework that gives an O(√nα(n))-approximation for polygonal obstacles, where α(n) denotes the inverse Ackermann’s function. For pseudodisks and rectilinear polygons, the same technique achieves an O(√n)-approximation. The technique also gives O (√n)-approximation for the minimum color path problem in graphs. We also present some inapproximability results for the geometric constraint removal problem.  more » « less
Award ID(s):
1814172
PAR ID:
10168735
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Computational geometry
Volume:
90
ISSN:
1879-081X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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