note chipmunk Keeping in mind that this golf challenge asks for a program rather than a subroutine... :) <p> <b>48 characters</b>: <code>#!perl $m=pop;for$"(pop..$m){$_="@ARGV";-e||warn"$_\n"} </code> example usage: <code>perl missing.pl bar .jpg 0000 0050</code> <p> Hurrah for the range operator and magical auto-increment! <p> As best I can figure it, the only way to accurately accomplish the bonus (checking for a comparison string that's too big) is to check all the files in the directory. Otherwise there could be one file in there with a unique part of the right length. 82434 82434