Well, this smells like homework, but I'd do it like this: 
use strict;
my $head;
my %hash;
while (<>) {
    $head = (split)[0];
    push @{$hash{$head}}, $_;
}

[download]
Update: Sigh. I'm late.



Code is (almost) always untested.
http://www.justicepoetic.net/

In reply to Re: pushing similar lines into arrays by jweed
in thread pushing similar lines into arrays by Phydro

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