you're on unix/linux right? 
sort input.txt | uniq

[download]
or if you want the counts of the unique input lines 
sort input.txt | uniq -c

[download]
or is this (perl) homework?
the hardest line to type correctly is: stty erase ^H

In reply to Re: Braino - why is this not working? by aquarium
in thread Braino - why is this not working? by perl-diddler

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