My previous post was a non-sequitur, sorry. It would be easier if the dealer wasn't colour-blind. We could factor in the backs. 
#!/usr/bin/perl -w
# Re-sorting a pile of four decks. Unfazed by missing cards.
# Using tr to avoid the unfathomable card-sort map.

# Mock names for easy sorting
my @suit = qw(f g h i);
my @rank = (2..9, qw(a b c d e));
my @pile= ();

sub shuffle { 
    for (my $i = $#_ ; $i > 0 ; $i--) {
        @_[$_, $i] = @_[$i, $_] for rand $i+1
    } return @_;
}
sub readable {
    my $string = join(" ", @_);
    $string =~ tr/abcdefghi/TJQKACDHS/;
    return $string;
}
sub separate {
    my @cards = sort @_;
    my @box = (); my $deck = 0; my $prevcard = "";
    for my $card (@cards) {
        if ($card ne $prevcard) {$deck = 0};
        push @{$box[$deck++]}, $card;
        $prevcard = $card;
    }
    return @box;
}

for (1..4) {
    push (@pile, (map {$rank = $_; map {"$_$rank"} @suit} @rank));
}
shuffle @pile;
print "\nFour decks shuffled together\n";
print (readable @pile);
my @decks = separate @pile;
print "\n\nFour decks separated\n";
foreach (@decks) {
    print (readable @$_);
    print "\n";
}

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In reply to Re^2: 52 Perl Pickup by Upstairs
in thread 52 Perl Pickup by dogz007

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