You should try to make a little bit of effort to arrive at a solution on your own, at least say "This is what I've tried but it doesn't work and I don't know why".

Your task can be solved by reading the file in a loop, using split on each line and then putting the first returned element into a hash as a key (for example $hash{$element}=1. After you read the whole file you can open another file for writing and do

for my $name(keys %hash) {
  print $filehandle "$name\n";
}

[download]

Try to solve it with that information and do come back and ask if you have problems.


Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it. -- Brian W. Kernighan

In reply to Re: output unique lines only by tirwhan
in thread output unique lines only by sbp

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