have spent so much time for this pgm with unfruitful results please help me with it
It would be best to post what you have tried so far. Post your code and input data inside "code" tags to make your post more readable (Writeup Formatting Tips).

Perl has great documentation available on your command line: 

perldoc -q duplicate

[download]

You should try to use a hash. See also perldsc.

In reply to Re: eliminating duplicates with filters by toolic
in thread eliminating duplicates with filters by snow28

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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