#!/usr/bin/perl -w
use strict;
use Data::Dumper;

# While matching the hash, elem of each array must occur together
# and in order

my @ar1   = ('A','B');      #Answer: 3
my @ar2   = ('B','A');      #Answer: 1
my @ar3   = ('A','B','C');  #Answer: 2

my $hash = {
            'S1' => [ 'A', 'B', 'C', 'A' ],
            'S2' => [ 'A', 'C', 'D', 'B' ],
            'S3' => [ 'C', 'A', 'D', 'H' ],
            'S4' => [ 'A', 'B', 'I', 'C' ]
           };

print "Total Support: ", count_support_order_based($hash,\@ar1), "\n";
print "Total Support: ", count_support_order_based($hash,\@ar2), "\n";

sub count_support_order_based
{
    my ($hash,$array) = @_;
    my $tmp_support;
    my $support;
    my $total_support;

    my $array_string = join("", @{$array});
    
    for my $key ( keys %{$hash}  )
    {
        my $hash_string = join("",@{$hash->{$key}} );
        $tmp_support = () = $hash_string =~ m/[\Q$array_string\E]/g;

        $support = sprintf("%.0d", 
                            $tmp_support/ (length $array_string));

        print "$support - $hash_string\n";
        if ( $support )
        {
         $total_support += $support;
        }
    }                               # -----  end foreach  -----


    return $total_support;
}

##</code><code>##

Substring to Count: AB   |  Substring to Count: BA   
                         |
1 - ABCA                 |  1 - ABCA
1 - ACDB                 |  1 - ACDB
1 - ABIC                 |  1 - ABIC
  - CADH                 |    - CADH
Total Support: 3         | Total Support: 3
 **CORRECT**                **WRONG**

##</code><code>##

Substring to Count: BA
1 - ABCA
0 - ACDB
0 - ABIC
  - CADH
Total Support: 1