in reply to Hash Multiple values for a key-Filtering unique values for a key in hash

Hello rahulme81,

Another approach is to store each set of values in its own hash, rather than in an array:

use strict;
use warnings;
use Data::Dump;

my $HASH1 =
{
    'Alabama'    => ['Andalusia', 'Anniston', 'Clanton', 'Eufaula', 'A
+uburn',
                     'Bessemer',  'Eufaula',  'Auburn',  'Bessemer' ],
    'California' => ['Barstow',   'Barstow'],
    'Georgia'    => ['Darien'],
    'New York'   => ['Amsterdam', 'Coney Island', 'Coney Island', 'Bea
+con', 'Becon']
};

print "Values stored in anonymous arrays:\n";
dd $HASH1;
my $HASH2;

for my $key (keys %$HASH1)
{
    ++$HASH2->{$key}{$_} for @{ $HASH1->{$key} };
}

print "\nValues stored in anonymous hashes:\n";
dd $HASH2;

[download]

Output:

13:39 >perl 1780_SoPW.pl
Values stored in anonymous arrays:
{
  "Alabama"    => [
                    "Andalusia",
                    "Anniston",
                    "Clanton",
                    "Eufaula",
                    "Auburn",
                    "Bessemer",
                    "Eufaula",
                    "Auburn",
                    "Bessemer",
                  ],
  "California" => ["Barstow", "Barstow"],
  "Georgia"    => ["Darien"],
  "New York"   => ["Amsterdam", "Coney Island", "Coney Island", "Beaco
+n", "Becon"],
}

Values stored in anonymous hashes:
{
  "Alabama"    => {
                    Andalusia => 1,
                    Anniston  => 1,
                    Auburn    => 2,
                    Bessemer  => 2,
                    Clanton   => 1,
                    Eufaula   => 2,
                  },
  "California" => { Barstow => 2 },
  "Georgia"    => { Darien => 1 },
  "New York"   => { "Amsterdam" => 1, "Beacon" => 1, "Becon" => 1, "Co
+ney Island" => 2 },
}

13:39 >

[download]

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In Section Seekers of Perl Wisdom