Найти скалярное и векторное произведение векторов

#include <stdio.h>
#include <iostream.h>
#include <math.h>
 
class TVector3D
{
private:
double x,y,z;
 
public:
TVector3D(double a,double b,double c):x(a),y(b),z(c) {}
TVector3D() {}
TVector3D() {}
TVector3D TVector3D::operator + (TVector3D &c) 
{
TVector3D t;
t.x = x + c.x;
t.y = y + c.y;
t.z = z + c.z;
return t;
}
TVector3D TVector3D::operator - (TVector3D &c) 
{
TVector3D t;
t.x = x + c.x;
t.y = y + c.y;
t.z = z + c.z;
return t;
}
double TVector3D::operator * (TVector3D &c) 
{
return x*c.x+y*c.y+z*c.z;
}
TVector3D TVector3D::operator / (TVector3D &c) 
{
TVector3D t;
t.x = y*c.z - z*c.y;
t.y = -(x*c.z-z*c.x);
t.z = z*c.y - y*c.x;
return t;
}
double abs();
void print();
double multi(TVector3D,TVector3D);
};
 
double TVector3D::multi(TVector3D b,TVector3D c)
{
double t;
t=x*b.x*c.z-x*b.z*c.y-y*b.x*c.z+y*b.z*c.x+z*b.x*c.y-z*b.y*c.x;
return t;
}
 
double TVector3D::abs()
{
return sqrt(x*x+y*y+z*z);
}
 
void TVector3D:rint()
{
printf("V=i*%lf+j*%lf+k*%lf \n",x,y,z);
}
 
void main()
{
double x,y,z;
cout<<"input vector a: "; cin>>x>>y>>z; TVector3D a(x,y,z);
cout<<"input vector b: "; cin>>x>>y>>z; TVector3D b(x,y,z);
cout<<"input vector c: "; cin>>x>>y>>z; TVector3D c(x,y,z);
TVector3D t;
t=a+b;
t.print();
printf("%lf \n",a*b);
t=a/b;
t.print();
printf("%lf \n",a.abs());
printf("%lf \n",a.multi(b,c));
return 0;}