in reply to Re: Shorten a list...
in thread Shorten a list...

Thanks so much for all of the feedback. As I have been working on this, the format has been changed so that the original input list now looks like:

Group 1
name
Group 2
name
Group 3
name
name
Group 4
name
Group 5
name
name
name

Your suggestions so far have been really helpful. Can anyone help me now with trying to only print the groups with multiple entries (Group 3 and Group 5) in this format:

Group 3
name
name

Group 5
name
name
name

Again, your help is greatly appreciated

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Re^3: Shorten a list...
by Cristoforo (Curate) on Oct 17, 2011 at 21:30 UTC
    There may be other ways than this. If the file is large (MB or GB), you might not want this method. It reads the whole file into an array, @data, before printing. 
    #!/usr/bin/perl
use strict;
use warnings;

my (@buffer, @data);
while (<DATA>) {
    if (/^Group/) {
        push @data, [@buffer] if @buffer > 2;
        @buffer = $_;   
    }
    else {
        push @buffer, $_;   
    }
}

push @data, [@buffer] if @buffer > 2;

{
    local $" = '';
    print join("\n", map "@$_", @data);
}

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      Thanks for the response. I have tried this script and still have the singlets being printed. Is there a way to get rid of the singlets (eg. only print groups 3 and 5 final output)?

[reply]
        My code ran fine on the sample you provided. Is this exactly how the file looks? 
        __DATA__
Group 1
name
Group 2
name
Group 3
name
name
Group 4
name
Group 5
name
name
name
Group 11
name
name
Group 15
name
name
name

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