Loading…
Ranking and unranking permutations in linear time
A ranking function for the permutations on n symbols assigns a unique integer in the range [0,n!−1] to each of the n! permutations. The corresponding unranking function is the inverse: given an integer between 0 and n!−1, the value of the function is the permutation having this rank. We present simp...
Saved in:
Published in: | Information processing letters 2001-09, Vol.79 (6), p.281-284 |
---|---|
Main Authors: | , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | A
ranking function for the permutations on
n symbols assigns a unique integer in the range
[0,n!−1] to each of the
n! permutations. The corresponding
unranking function is the inverse: given an integer between
0 and
n!−1, the value of the function is the permutation having this rank. We present simple ranking and unranking algorithms for permutations that can be computed using
O(n)
arithmetic operations. |
---|---|
ISSN: | 0020-0190 1872-6119 |
DOI: | 10.1016/S0020-0190(01)00141-7 |