Some Performance Tests of "quicksort" and Descendants Detailed performance evaluations are presented for six ACM algorithms: quicksort (No. 64), Shellsort (No. 201), stringsort (No. 207), "TREESORT3" (No. 245), quickersort (No. 271), and qsort (No. 402). Algorithms 271 and 402 are refinements of algorithm 64, and all three are discussed in some detail. The evidence given here demonstrates that qsort (No. 402) requires many more comparisons than its author claims. Of all these algorithms, quickersort requires the fewest comparisons to sort random arrays. CACM March, 1974 Loeser, R. sorting, in-place sorting, sorting efficiency, sorting performance tests, quicksort, quickersort, qsort, Shellsort, stringsort, TREESORT3,utility sort algorithm, general-purpose sort algorithm, sorting algorithm documentation 4.49 5.31 CA740304 JB January 18, 1978 11:26 AM 1175 4 2679 1663 4 2679 1919 4 2679 1919 4 2679 1919 4 2679 1969 4 2679 1969 4 2679 1997 4 2679 1997 4 2679 2042 4 2679 2042 4 2679 2118 4 2679 2191 4 2679 2195 4 2679 2216 4 2679 2216 4 2679 2222 4 2679 2222 4 2679 2356 4 2679 2388 4 2679 2348 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2679 4 2679 2844 4 2679 2972 4 2679 3054 4 2679 3054 4 2679 3054 4 2679 3054 4 2679 3121 4 2679 970 5 2679 1175 5 2679 1190 5 2679 1228 5 2679 1969 5 2679 1997 5 2679 308 5 2679 2042 5 2679 2679 5 2679 2679 5 2679 2679 5 2679 507 5 2679 3054 5 2679 3187 5 2679 716 5 2679 783 5 2679 1175 6 2679 1880 6 2679 1919 6 2679 1969 6 2679 1980 6 2679 1997 6 2679 307 6 2679 308 6 2679 309 6 2679 2017 6 2679 2679 6 2679 776 6 2679