A Hash of arrays may fit the bill for you:

use strict;
use warnings;
use Data::Dumper;

my %HoA;

while (<DATA>)
  {
  chomp;
  next if ! length $_;
  my ($key, $time) = split ",";
  push @{$HoA{$key}}, $time;
  }
  
print Dumper (%HoA);

[download]
  
__DATA__
KEY1, 07/25/05 09:04:36
KEY2, 07/25/05 09:04:36
KEY2, 07/25/05 09:04:37
KEY2, 07/25/05 09:05:49
KEY2, 07/25/05 09:05:50
KEY3, 07/25/05 09:05:50

$VAR1 = 'KEY2';
$VAR2 = [
          ' 07/25/05 09:04:36',
          ' 07/25/05 09:04:37',
          ' 07/25/05 09:05:49',
          ' 07/25/05 09:05:50'
        ];
$VAR3 = 'KEY1';
$VAR4 = [
          ' 07/25/05 09:04:36'
        ];
$VAR5 = 'KEY3';
$VAR6 = [
          ' 07/25/05 09:05:50'
        ];

[download]
Perl is Huffman encoded by design.

In reply to Re^5: Perl Hash by GrandFather
in thread Perl Hash by TechNoFear

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