sub addU {
    my ($self, $item) = @_;
    my $key = $item->{key};

    if (! exists $self->{$key}) {
        $self->{$key} = pack ('NN', 1, $item->{cond});
    } else {
        my ($count, $flag) = unpack ('NN', $self->{$key});
        $self->{$key} = pack ('NN', $count + 1, $flag || $item->{cond});
    }
}


sub getFlagU {
    return (unpack ('NN', $_[0]->{$_[1]}))[1];
}


sub getCountU {
    return (unpack ('NN', $_[0]->{$_[1]}))[0];
}


sub addA {
    my ($self, $item) = @_;
    my $key = $item->{key};

    if (! exists $self->{$key}) {
        $self->{$key} = [1, $item->{cond}]
    } else {
        $self->{$key}[0]++;
        $self->{$key}[1] ||= $item->{cond};
    }
}


sub getFlagA {
    return $_[0]->{$_[1]}[1];
}


sub getCountA {
    return $_[0]->{$_[1]}[0];
}


sub addI {
    my ($self, $item) = @_;
    my $key = $item->{key};

    if (! exists $self->{$key}) {
        $self->{$key} = 2 | !!$item->{cond};
    } else {
        $self->{$key} += 2;
        $self->{$key} |= !!$item->{cond};
    }
}


sub getFlagI {
    return int ($_[0]->{$_[1]} & 1);
}


sub getCountI {
    return int ($_[0]->{$_[1]} / 2);
}