eng
Schloss Dagstuhl – Leibniz-Zentrum für Informatik
Leibniz International Proceedings in Informatics
1868-8969
2017-12-07
66:1
66:12
10.4230/LIPIcs.ISAAC.2017.66
article
A (1.4 + epsilon)-Approximation Algorithm for the 2-Max-Duo Problem
Xu, Yao
Chen, Yong
Lin, Guohui
Liu, Tian
Luo, Taibo
Zhang, Peng
The maximum duo-preservation string mapping (Max-Duo) problem is
the complement of the well studied minimum common string partition (MCSP) problem, both of which have applications in many fields including text compression and bioinformatics. k-Max-Duo is the restricted version of Max-Duo, where every letter of the alphabet occurs at most k times in each of the strings, which is readily reduced into the well known maximum independent set (MIS) problem on a graph of maximum degree \Delta \le 6(k-1). In particular, 2-Max-Duo can then be approximated arbitrarily close to 1.8 using the state-of-the-art approximation algorithm for the MIS problem. 2-Max-Duo was proved APX-hard and very recently a (1.6 + \epsilon)-approximation was claimed, for any \epsilon > 0. In this paper, we present a vertex-degree reduction technique, based on which, we show that 2-Max-Duo can be approximated arbitrarily close to 1.4.
https://drops.dagstuhl.de/storage/00lipics/lipics-vol092-isaac2017/LIPIcs.ISAAC.2017.66/LIPIcs.ISAAC.2017.66.pdf
Approximation algorithm
duo-preservation string mapping
string partition
independent set