Programming Improvements to Fike's Algorithm for Generating Permutations

In a recent number of this Journal, Fike (1975) has given a new algorithm for generating permutations, which his experiments indicate is comparable with the fastest known methods (see Ord-Smith, 1970 and 1971). In this paper we consider some programming modifications to the procedures Fike presents which improve the performance by a factor of about 2. The timings show that with a compiler which handles procedure calls reasonably, a recursive procedure is the most efficient.