Lektion3_4

class Binary_Operator
{
public:
  //virtual double evaluate(double a, double b) const { return 0.0; }
  virtual double evaluate(double a, double b) const = 0;

};

class Multiply : public Binary_Operator
{
public:
  double evaluate(double a, double b) const override { return a * b; }
};

class Add : public Binary_Operator
{
public:
  double evaluate(double a, double b) const override { return a + b; }
};

int main()
{
  //vector<Binary_Operator> v{ Multiply{}, Add{} };
  vector<Binary_Operator*> v{ new Multiply{}, new Add{} };

  for ( int i{0}; i < v.size(); ++i )
  {
    //cout << v[0].evaluate(5.0, 3.0) << endl;
    cout << v[i].evaluate(5.0, 3.0) << endl;
  }
  return 0;
}