note DrManhattan <p>Read further down in the <a href="http://www.hpl.hp.com/personal/Larry_Rosler/sort/sorting.html">Guttman/Rosler</a> paper to where they discuss the "packed-default" sort:</p> <code> @out = map substr($_, 4) => sort map pack('C4' => /(\d+)\.(\d+)\.(\d+)\.(\d+)/) . $_ => @in; </code> <p>The idea is to pack the entire list once before sorting it then get each address back out with a substr afterwards. Using this technique, you only make N packs and N substrs, instead of N*log(N) packs. It also has the advantage of using sort without calling a subroutine for each comparison which is a huge speedup.</p> <p>-Matt</p> 25833 25833