A quadratic time 2-approximation algorithm for block sorting
نویسندگان
چکیده
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 recognition (OCR) and is related to transposition sorting in computational biology.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 410 شماره
صفحات -
تاریخ انتشار 2009