Combination Generators

Abstract
The Liu-Tang combmatmn enumeratmn algonthm produces a cychc sequence of combinations. Each combination is obtained from Its predecessor by a single exchange of two marks. History of the sequence does not need to be known to generate the next comblnatmn. A pointer programmed versmn of the Lm-Tang algorithm greatly improves speed of execution compared to the original coding when K or N - K Is small as they appear m ~). This implementation was rated with respect to advantageous attributes and compared favorably with several other combination enumeratmn algorithms