Minimizing the maximum bump cost in linear extensions of a poset

Author: Wu Biao   Liu Longcheng   Yao Enyu  

Publisher: Springer Publishing Company

ISSN: 1382-6905

Source: Journal of Combinatorial Optimization, Vol.26, Iss.3, 2013-10, pp. : 509-519

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

A linear extension of a poset P=(X,≺) is a permutation x 1,x 2,…,x |X| of X such that i<j whenever x i x j . For a given poset P=(X,≺) and a cost function c(x,y) defined on X×X, we want to find a linear extension of P such that maximum cost is as small as possible. For the general case, it is NP-complete. In this paper we consider the linear extension problem with the assumption that c(x,y)=0 whenever x and y are incomparable. First, we prove the discussed problem is polynomially solvable for a special poset. And then, we present a polynomial algorithm to obtain an approximate solution.