Approximation algorithms for maximum two-dimensional pattern matching
نویسندگان
چکیده
منابع مشابه
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The problem of computing a matching of maximum weight in a given edge-weighted graph is not known to be P-hard or in RNC. This paper presents four parallel approximation algorithms for this problem. The rst is an RNC-approximation scheme, i.e., an RNC algorithm that computes a matching of weight at least 1 times the maximum for any given constant > 0. The second one is an NC approximation algor...
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We consider the problem of computing a matching in a large weighted graph using a parallel algorithm. Since an exact algorithm for the weighted matching problem is fairly costly we instead develop a fast approximation algorithm. The parallel algorithm is based on a distributed algorithm due to Hoepman [6]. Through experiments using both complete as well as sparse graphs we show that our new alg...
متن کاملParallel Approximation Algorithms for Maximum Weighted Matching in General Graphs
The problem of computing a matching of maximum weight in a given edge-weighted graph is not known to be P-hard or in RNC. This paper presents four parallel approximation algorithms for this problem. The first is an RNC-approximation scheme, i.e., an RNC algorithm that computes a matching of weight at least 1 − times the maximum for any given constant > 0. The second one is an NC approximation a...
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An algorithm for searching for a two dimensional m m pattern in a two dimensional n n text is presented. It performs on the average less comparisons than the size of the text: n 2 =m using m 2 extra space. Basically, it uses multiple string matching on only n=m rows of the text. It runs in at most 2n 2 time and is close to the optimal n 2 time for many patterns. It steadily extends to an alphab...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2001
ISSN: 0304-3975
DOI: 10.1016/s0304-3975(99)00153-x