TY - GEN
T1 - Restricted LCS
AU - Gotthilf, Zvi
AU - Hermelin, Danny
AU - Landau, Gad M.
AU - Lewenstein, Moshe
PY - 2010/11/24
Y1 - 2010/11/24
N2 - The Longest Common Subsequence (LCS) of two or more strings is a fundamental well-studied problem which has a wide range of applications throughout computational sciences. When the common subsequence must contain one or more constraint strings as subsequences, the problem becomes the Constrained LCS (CLCS) problem. In this paper we consider the Restricted LCS (RLCS) problem, where our goal is finding a longest common subsequence between two or more strings that does not contain a given set of restriction strings as subsequences. First we show that in case of two input strings and an arbitrary number of restriction strings the RLCS problem is NP-hard. Afterwards, we present a dynamic programming solution for RLCS and we show that this algorithm implies that RLCS is in FPT when parameterized by the total length of the restriction strings. In the last part of this paper we present two approximation algorithms for the hard variants of the problem.
AB - The Longest Common Subsequence (LCS) of two or more strings is a fundamental well-studied problem which has a wide range of applications throughout computational sciences. When the common subsequence must contain one or more constraint strings as subsequences, the problem becomes the Constrained LCS (CLCS) problem. In this paper we consider the Restricted LCS (RLCS) problem, where our goal is finding a longest common subsequence between two or more strings that does not contain a given set of restriction strings as subsequences. First we show that in case of two input strings and an arbitrary number of restriction strings the RLCS problem is NP-hard. Afterwards, we present a dynamic programming solution for RLCS and we show that this algorithm implies that RLCS is in FPT when parameterized by the total length of the restriction strings. In the last part of this paper we present two approximation algorithms for the hard variants of the problem.
UR - http://www.scopus.com/inward/record.url?scp=78449292478&partnerID=8YFLogxK
U2 - 10.1007/978-3-642-16321-0_26
DO - 10.1007/978-3-642-16321-0_26
M3 - Conference contribution
AN - SCOPUS:78449292478
SN - 3642163203
SN - 9783642163203
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 250
EP - 257
BT - String Processing and Information Retrieval - 17th International Symposium, SPIRE 2010, Proceedings
T2 - 17th International Symposium on String Processing and Information Retrieval, SPIRE 2010
Y2 - 11 October 2010 through 13 October 2010
ER -