Linear-Time Ranking of Permutations

نویسندگان

  • Martin Mares
  • Milan Straka
چکیده

A lexicographic ranking function for the set of all permutations of n ordered symbols translates permutations to their ranks in the lexicographic order of all permutations. This is frequently used for indexing data structures by permutations. We present algorithms for computing both the ranking function and its inverse using O(n) arithmetic operations.

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تاریخ انتشار 2007