A quadratic time 2-approximation algorithm for block sorting
نویسندگان
چکیده
منابع مشابه
A quadratic time 2-approximation algorithm for block sorting
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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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 2009
ISSN: 0304-3975
DOI: 10.1016/j.tcs.2008.10.022