public class DeluxeSleigh extends Sleigh {

    DeluxeSleigh() {
        super(3500, 1200);
    }

    void harness(Reindeer r) throws Exception {
        if (this.reindeer.size() >= 4) {
            throw new Exception();
        }
        super.harness(r);
    }

    double getSpeed() {
        return super.getSpeed() + 2.5;
    }
}