An Improved Approximation Algorithm for the Complementary Maximal Strip Recovery Problem
نویسندگان
چکیده
Given two genomic maps G1 and G2 each represented as a sequence of n gene markers, the maximal strip recovery (MSR) problem is to retain the maximum number of markers in both G1 and G2 such that the resultant subsequences, denoted as G ∗ 1 and G ∗ 2, can be partitioned into the same set of maximal strips, which are common substrings of length greater than or equal to two. The complementary maximal strip recovery (CMSR) problem has the complementary goal to delete the minimum number of markers. Both MSR and CMSR have been shown NP-hard and APX-complete, and they admit a 4-approximation and a 3-approximation respectively. In this paper, we present an improved 7 3 -approximation algorithm for the CMSR problem, with its worst-case performance analysis done through a sequential amortization.
منابع مشابه
Exact and approximation algorithms for the complementary maximal strip recovery problem
Given two genomic maps G1 and G2 each represented as a sequence of n gene markers, the maximal strip recovery (MSR) problem is to retain the maximum number of markers in both G1 and G2 such that the resultant subsequences, denoted as G ∗ 1 and G∗ 2 , can be partitioned into the same set of maximal substrings of length greater than or equal to two. Such substrings can occur in the reversal and n...
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Given two genomic maps G and H represented by a sequence of n gene markers, a strip (syntenic block) is a sequence of distinct markers of length at least two which appear as subsequences in the input maps, either directly or in reversed and negated form. The problem Maximal Strip Recovery (MSR) is to find two subsequences G' and H' of G and H, respectively, such that the total length of disjoin...
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