Block Sorting is Hard
نویسندگان
چکیده
منابع مشابه
On Approximability of Block Sorting
Block Sorting is a well studied problem, motivated by its applications in Optical Character Recognition (OCR), and Computational Biology. Block Sorting has been shown to be NP-Hard, and two separate polynomial time 2-approximation algorithms have been designed for the problem. But questions like whether a better approximation algorithm can be designed, and whether the problem is APX-Hard have b...
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We give an approximation algorithm for the block sorting problem with an approximation ratio of 2 and run time O(n). The approximation algorithm is based on the related concept of block deletion. We show that finding an optimum block deletion sequence can be done in O(n) time, while block sorting is known to be NP-hard. Block sorting has importance in connection with optical character recogniti...
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Block sorting is used in connection with optical character recognition (OCR). Recent work has focused on finding good strategies which perform well in practice. Block sorting is NP-hard and all of the previously known heuristics lack proof of any approximation ratio. We present here an approximation algorithm for the block sorting problem with approximation ratio of 2 and run time O(n). The app...
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Given a permutation π, the problem is to find a shortest series of block moves which, when applied in succession, sorts π. Here a block is a maximal substring of successive integers in order, and a block move is the displacement of a block to a location where it merges with another block. is an NP-hard optimization problem [3] and has a factor 2 approximation algorit...
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ورودعنوان ژورنال:
- Int. J. Found. Comput. Sci.
دوره 14 شماره
صفحات -
تاریخ انتشار 2002