Sorting by Length-Weighted Reversals: Dealing with Signs and Circularity
نویسندگان
چکیده
We consider the problem of sorting linear and circular permutations and 0/1 sequences by reversals in a length-sensitive cost model. We extend the results on sorting by length-weighted reversals in two directions: we consider the signed case for linear sequences and also the signed and unsigned cases for circular sequences. We give lower and upper bounds as well as guaranteed approximation ratios for these three cases. The main result in this paper is an optimal polynomial-time algorithm for sorting circular 0/1 sequences when the cost function is additive.
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