public abstract class SS11_2 {
    private final int wissen;
    
    public SS11_2(int wissensstand) {
        wissen = wissensstand;
    }
    
    public int getWissen() {
        return wissen;
    }
    
    public double eval() {
        return ((1 + (int) Math.random()*5) + wissen) / 2;
    }
}

class Student extends SS11_2 {
    public Student() {
        super(3);
    }
}

class Studentin extends SS11_2 {
    public Studentin() {
        super(1);
    }
}