#!/usr/bin/perl -w
use strict;

use Data::Dump qw(pp);

my @all_arrays = ([1 .. 20],
                  [10 .. 30],
                  [19 .. 40],
                 );

my %unique_descriptive;

foreach my $num (map{@$_}@all_arrays)
{
   $unique_descriptive{$num}{count}++;
   push @{$unique_descriptive{$num}{values}}, $num;
}

#print pp(\%unique_descriptive);  

# example for num=10
#10 => { count => 2, "values" => [10, 10] },

my @sorted_keys = sort{ $unique_descriptive{$a}{count} <=> $unique_descriptive{$b}{count} 
                                                        or
                                                     $a <=> $b
                      }keys %unique_descriptive;

foreach my $key (@sorted_keys)
{
   printf "%2d=", $key;   #make the print out look nice
   print pp($unique_descriptive{$key}),"\n";
}

__END__