As mentioned in the chatterbox, you wanted to sort by the first element of the array rather than by the hash key. This example will work:

use strict;
use warnings;

my %hash = (
            1    => [1, 'One'],
            2    => [2, 'Two'],
            3    => [3, 'Three'],
            4    => [4, 'Four'],
            5    => [5, 'Five'],
            6    => [6, 'Six'],
            12   => [12, 'Twelve'],
           );

# sort the hash numerically by the first element in each array
foreach my $key ( sort { $hash{$a}[0] <=> $hash{$b}[0] } keys %hash )
{
    print "Integer is: $key -- Alpha is: $hash{$key}[1]\n";
}
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Please also note that if you had warnings turned on you would have realized the second element in your arrays are barewords and need to be quoted.

Relevant links:

• sort
• perlref
• the QandASection: sorting section in Categorized Questions and Answers
• How do I sort a hash of arrays by value THEN by key? (and similar), found by Super Search

sort { $a <=> $b } @sort
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here the Solution:

my %hash = (
            1    => [1, One],
            2    => [2, Two],
            3    => [3, Three],
            4    => [4, Four],
            5    => [5, Five],
            6    => [6, Six],
            12    => [12, Twelve],
           );


my @sort;
for my $key (sort (keys %hash)) {
   push @sort, "$hash{$key}[0]::$hash{$key}[1]";
}

    my @new = sort { $a <=> $b } @sort;
    
for (@new) {
   my ($int, $alpha) = split(/::/, $_);
   print "Integer is: $int -- Alpha is: $alpha\n";
}
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regards,
Franklin

#!/usr/bin/perl -w

use strict;
use Data::Dumper;

my %hash = (
            'a'    => [1, 'One'],
            'b'    => [2, 'Two'],
            'c'    => [3, 'Three'],
            'd'    => [4, 'Four'],
            'e'    => [5, 'Five'],
            'f'    => [6, 'Six'],
            'g'    => [12, 'Twelve'],
);

my %key_ht;
foreach my $key (keys %hash) { $key_ht{$hash{$key}[0]} = $key }

# print "key_ht:", Dumper(\%key_ht), "\n";

foreach my $key (sort { $a <=> $b } keys %key_ht) {

    my $num = $hash{$key_ht{$key}}[0];
    my $str = $hash{$key_ht{$key}}[1];
    print "Integer is: ", $num, " -- Alpha is: ", $str, "\n";
}
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Integer is: 1 -- Alpha is: One
Integer is: 2 -- Alpha is: Two
Integer is: 3 -- Alpha is: Three
Integer is: 4 -- Alpha is: Four
Integer is: 5 -- Alpha is: Five
Integer is: 6 -- Alpha is: Six
Integer is: 12 -- Alpha is: Twelve
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See also our wonderful Tutorials section, including the following (in no particular order):

Complex sorting
Understanding transformation sorts (ST, GRT), the details
Resorting to Sorting

HTH,

I also recommend "A Fresh Look at Efficient Perl Sorting" by Uri Guttman and Larry Rosler.
http://www.sysarch.com/perl/sort_paper.html

It talks about performance but I found it interesting because it explains different samples of sorting code.

#!/usr/bin/perl
$\="\n";
my %hash = (
            1    => "One",
            2    => "Two",
            3    => "Three",
            4    => "Four",
            5    => "Five",
            6    => "Six",
            12   => "Twelve",
           );
   print "Integer is: $_ -- Alpha is: $hash{$_}" for (sort {$a <=> $b}
+ keys %hash)
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