arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2007.08204cs.DS
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基于加性组合数学的常数箱子装箱问题的一个更快指数时间算法

A Faster Exponential Time Algorithm for Bin Packing With a Constant Number of Bins via Additive Combinatorics

Jesper Nederlof, Jakub Pawlewicz, Céline M. F. Swennenhuis, Karol Węgrzycki

AI总结:

本文针对常数箱子Bin Packing问题,利用加性组合数学中的Littlewood-Offord理论新结果,设计了时间复杂度优于$\mathcal{O}^\star(2^n)$的随机化算法。

摘要:

在Bin Packing问题中,给定$n$个权重为$w_1,\ldots,w_n$的物品和$m$个容量为$c_1,\ldots,c_m$的箱子。目标是将物品划分为集合$S_1,\ldots,S_m$,使得对每个箱子$j$满足$w(S_j) \leq c_j$,其中$w(X)$表示$\sum_{i \in X}w_i$。Björklund、Husfeldt和Koivisto(SICOMP 2009)提出了一个$\mathcal{O}^\star(2^n)$时间的Bin Packing算法。本文证明,对于任意$m \in \mathbf{N}$,存在常数$σ_m >0$,使得具有$m$个箱子的Bin Packing实例可在$\mathcal{O}(2^{(1-σ_m)n})$随机时间内求解。此前,即便$m$等于$4$时也未知此类改进算法。本方法的关键步骤是关于子集和加性组合数学的Littlewood-Offord理论的新结果:对任意$δ>0$,存在$\varepsilon >0$,若对某$v$满足$|\{ X\subseteq \{1,\ldots,n \} : w(X)=v \}| \geq 2^{(1-\varepsilon)n}$,则$|\{ w(X): X \subseteq \{1,\ldots,n\} \}|\leq 2^{δn}$。

英文摘要:

In the Bin Packing problem one is given $n$ items with weights $w_1,\ldots,w_n$ and $m$ bins with capacities $c_1,\ldots,c_m$. The goal is to find a partition of the items into sets $S_1,\ldots,S_m$ such that $w(S_j) \leq c_j$ for every bin $j$, where $w(X)$ denotes $\sum_{i \in X}w_i$. Björklund, Husfeldt and Koivisto (SICOMP 2009) presented an $\mathcal{O}^\star(2^n)$ time algorithm for Bin Packing. In this paper, we show that for every $m \in \mathbf{N}$ there exists a constant $σ_m >0$ such that an instance of Bin Packing with $m$ bins can be solved in $\mathcal{O}(2^{(1-σ_m)n})$ randomized time. Before our work, such improved algorithms were not known even for $m$ equals $4$. A key step in our approach is the following new result in Littlewood-Offord theory on the additive combinatorics of subset sums: For every $δ>0$ there exists an $\varepsilon >0$ such that if $|\{ X\subseteq \{1,\ldots,n \} : w(X)=v \}| \geq 2^{(1-\varepsilon)n}$ for some $v$ then $|\{ w(X): X \subseteq \{1,\ldots,n\} \}|\leq 2^{δn}$.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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