static void Main(string[] args)
{
Mediator m = new Mediator();
Colleague head1 = new Colleague(m, "John");
ColleagueB branch1 = new ColleagueB(m, "David");
Colleague head2 = new Colleague(m, "Lucy");
head1.Send("Meeting on Tuesday, please all ack");
branch1.Send("Ack");
m.Block(branch1.Receive);
head1.Send("Still awaiting some Acks");
head2.Send("Ack");
m.Unblock(branch1.Receive);
head1.Send("Thanks all");
Console.ReadLine();
}
