use strict;
use List::Util qw(shuffle);

# construct a standard deck
my @card;
foreach my $suit (qw(H C S D)) {
    foreach my $value (2..10, qw(J Q K A)) {
        push @card, $value . $suit;
    }
}

# now shuffle us up a pile of cards, perhaps composed of any
# number of decks
my @pile;
my $n = 4;      # number of decks in shuffled pile
push @pile, @card for (1..$n);
@pile = shuffle @pile;


my $decks;
do {
		$decks = grab ( \@pile ); # split the pile into $n decks
		@pile = lookup( $decks ); # Look if we got it right..
} while ( @pile > 0 );
		

print "Got it!\n";

for my $a (0..$n){
		print "$_ " foreach ( @{$decks->{$a}} );
		print "\n\n";
}
# Exits here.. happily


sub grab{
		my $pile = shift;

		my $decks;
		# Grab the cards
		foreach my $card (@{$pile}){
				push @{$decks->{int(rand($n))}}, $card;
		}
		return $decks;
}

sub lookup{
		my $decks = shift;
		
		for my $a (0..$n-1) {
				my %cards; 
				foreach my $card ( @{$decks->{$a}} ){
						if ( defined( $cards{$card} ) ){
								damnit( $decks );
								return throw ( $decks );
						} else {
								$cards{$card} = 1; # Remember this. And dont forget it!
						}
				}
		}
}

sub damnit{
		my $decks = shift;

		print "Damnit!!!\n";
		for my $a (0..$n){
				print "$_ " foreach ( @{$decks->{$a}} );
				print "\n\n";
		}
}

sub throw{
		my $decks = shift;

		my @pile;
		foreach ( values %{$decks} ){
				push @pile, @{$_};
		}
		return shuffle( @pile );			
}