Re: string comparision in a file

From: Thomas Matthews (Thomas_MatthewsSpitsOnSpamBots_at_sbcglobal.net)
Date: 07/21/04 

Date: Wed, 21 Jul 2004 18:33:46 GMT

rakesh wrote:

> Hi,
> I have a requirement in which I need to search a string in a file
> stored on a harddisk. String which needs to be searched would be
> stored in a file with delimiter as new line character. some of the
> ways of doing this are
>
> 1. Read each line and do string compare immediately.
> 2. Read each line, add each string into a stl vector and search for
> the given string using stl bineary_search algorithm.
>
> It would be helpful if someone could give me comparison of which would
> be the best method among the above mentioned ways of handling
> searching. I would also welcome any other better of handling searching
> string in a file.
>
> Thanks,
> Rakesh.

If your system supports muli-tasking (multi-threading or whatever),
you could have one task reading lines into a buffer while another
task searches a given line.

This would assume that reading a line takes longer than searching it
and there is considerable overhead time when reading a line (such as
hard-drive start-up time, seeking time, etc.). Although these
timings usually only appear when the number of lines to read in
is huge; or the I/O overhead times are really slow.

Hmmm, why do things simple when you can have some fun making them
more complex? ;-) 

-- 
Thomas Matthews
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