class Triad
{
    double x,y,z;
public:
    Triad() {}
    Triad(double _x,double _y,double _z):x(_x),y(_y),z(_z) {}
    void Get(double & xx,double &yy,double &zz) {xx=x;yy=y;zz=z;}
    virtual void Set(double xx,double yy,double zz) {x=xx;y=yy;z=zz;}
};
class Triangle : public Triangle
{
public:
    class BadSideLengthException {};
    Triangle() {}
    bool bad_sides(double xx,yy,zz,)
    {
        return (x<0 || y<0 || z<0 || x>y+z || y>x+z || z>x+y);
    }
    Triangle(double _x,double _y,double _z):Triad(_x,_y,_z) {if (bad_sides(_x,_y,_z)) throw BadSideLengthException;}
    virtual void Set(double &xx,double &yy,double &zz)
    {
        if(bad_sides(xx,yy,zz))
            throw BadSideLengthException;
        x = xx;
        y = yy;
        z = zz;
    }
    double GetSquare()
    {

    }
    double GetAngleX()
    {
    }
        double GetAngleY()
    {
    }
            double GetAngleZ()
    {
    }
};