Polynomial-Time Approximation Schemes for Circle and Other Packing Problems

TL;DR

This paper introduces the first polynomial-time approximation schemes for circle packing problems, including minimum bin packing and strip packing, using novel iterative separation techniques and resource augmentation strategies.

Contribution

It presents the first asymptotic approximation schemes and resource augmentation methods for circle packing and related problems, extending to various shapes and higher dimensions.

Findings

First APTAS for circle bin packing and strip packing.

Resource augmentation scheme for packing with constant bb.

Extension to packing spheres in higher dimensions.

Abstract

We give an asymptotic approximation scheme (APTAS) for the problem of packing a set of circles into a minimum number of unit square bins. To obtain rational solutions, we use augmented bins of height $1+\gamma$, for some arbitrarily small number $\gamma > 0$. Our algorithm is polynomial on $\log 1/\gamma$, and thus $\gamma$ is part of the problem input. For the special case that $\gamma$ is constant, we give a (one dimensional) resource augmentation scheme, that is, we obtain a packing into bins of unit width and height $1+\gamma$ using no more than the number of bins in an optimal packing. Additionally, we obtain an APTAS for the circle strip packing problem, whose goal is to pack a set of circles into a strip of unit width and minimum height. These are the first approximation and resource augmentation schemes for these problems. Our algorithm is based on novel ideas of iteratively separating small and large items, and may be extended to a wide range of packing problems that satisfy certain conditions. These extensions comprise problems with different kinds of items, such as regular polygons, or with bins of different shapes, such as circles and spheres. As an example, we obtain APTAS's for the problems of packing d-dimensional spheres into hypercubes under the $L_p$-norm.