Lexicographic ordering, ranking and unranking of combinations
Author:
- 1 January 1985
- journal article
- research article
- Published by Taylor & Francis in International Journal of Computer Mathematics
- Vol. 17 (3-4) , 277-283
Abstract
A simple way of representing combinations as binary strings is discussed. The bijective mapping between the set of combinations and the set of corresponding binary codewords is shown to be isotone, in lexicographic order. A recursive algorithm for enumerating all combinations in lexicographic order is presented. Simple ranking and unranking algorithms for coding and decoding position indices of combinations in a lexicographic listing are also described.Keywords
This publication has 3 references indexed in Scilit:
- Factoring numbers in O(logn) arithmetic stepsInformation Processing Letters, 1979
- A numbering system for combinationsCommunications of the ACM, 1974
- Algorithm 94: CombinationCommunications of the ACM, 1962