package A;

use B;
use С;

sub new
{
    my $class = shift;
    my $opt = shift;

    my $self = {
        connect1 => DB->connect(1),
        connect2 => DB->connect(2),
        connect3 => DB->connect(3),
    };

    $self->{opt} = $opt;
    bless $self, $class;
}

sub start
{
    my $self = shift;

    if($self->{opt}->{B})
    {
        B->new($self)->start;
    }
    if($self->{opt}->{C})
    {
        C->new($self)->start;
    }
}

1;