Dan Muey wrote: > > Kevin Pfeiffer wrote: > > > > BTW, doesn't 'sort -u' also sort the list? > > sort -u opens a file and prints to STDOUT or another file the unique lines, > but that is an external command and not every server will necessariy have a > sort command and if it does -u may have a different meaning or it may not > exist at all.
If you have a list/file with a lot of duplicates then storing the list as hash keys and sorting those hash keys will be a LOT faster then using 'sort -u' because 'sort -u' has to sort the entire list first before it can remove duplicates while storing the list as hash keys removes the duplicates first leaving a much smaller list to sort. So for example if you have a list of 10,000 items of which only 10 are unique, 'sort -u' has to sort all 10,000 and then remove the duplicates while a perl hash would only have 10 items to sort. (Where the 'unique' part is O(n) and the 'sort' part is usually O(n log n).) John -- use Perl; program fulfillment -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
