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Open Problems

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Is there a faster algorithm for sorting signed permutations using reversals ?
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Given 3 signed permutations , find an efficient algorithm that minimizes (finding an exact solution is NP-hard [7]).
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Find the reversal distance between two signed digit sequences with equal number of occurrences of each digit.
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Find how many sequences of reversals realize d.
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Find among the minimum sequences one that has some additional properties.


Itshack Pe`er
1999-03-16