public class Gerade
{
    double m;
    double c;
    public Gerade(double _m, double _c)
    {
        m = _m;
        c = _c;
    }
    
    public Gerade( Punkt p1, Punkt p2)
    {
        m = (p2.y -p1.y) / (p2.x - p1.x);
        c = p1.y - m* p1.x;
    }
}