Как проинициализировать std::vector используя указатель на базовый массив?

 #include  

#include  

#include  

 

using namespace std; 

 

struct Shape { 

    virtual const char* name()const = 0; 

    virtual double area()const = 0; 

    virtual double perimeter()const = 0; 

protected: 

    inline static const auto pi = 3.141592653589793; 

}; 

 

class Circle : virtual public Shape { 

public: 

    Circle()  

        : r (0) {} 

    explicit Circle(const double r)  

        : r(r) {} 

    const char* name()const override { 

        return "circle"; 

    } 

    double area()const override { 

        return pi * r * r; 

    } 

    double perimeter()const override { 

        return 2.0 * pi * r; 

    } 

private: 

    double r; 

}; 

 

class Rectangle : virtual public Shape { 

public: 

    Rectangle()  

        : a(0), b(0) {} 

    Rectangle(const double a, const double b) 

        : a(a), b(b) {} 

    const char* name()const override { 

        return "rectangle"; 

    } 

    double area()const override { 

        return a * b; 

    } 

    double perimeter()const override { 

        return 2.0 * (a + b); 

    } 

private: 

    double a; 

    double b; 

}; 

 

class Triangle : virtual public Shape { 

public: 

    Triangle()  

        : a(0), b(0), c(0) {} 

    Triangle(const double a, const double b, const double c)  

        : a(a), b(b), c(c) {} 

    const char* name()const override { 

        return "triangle"; 

    } 

    double area()const override { 

        auto p = perimeter() / 2.0; 

        return sqrt(p * (p - a) * (p - b) * (p - c)); 

    } 

    double perimeter()const override { 

        return a + b + c; 

    } 

private: 

    double a; 

    double b; 

    double c; 

}; 

 

int main() { 

    Triangle ta{ 2.5, 3.7, 2.9 }; 

    Circle ca{ 1.85 }; 

    Rectangle ra{ 2.9, 4.8 }; 

    Triangle tb{ 3.2, 4.1, 2.5 }; 

    Circle cb{ 2.12 }; 

    Rectangle rb{ 4.85, 6.4 }; 

     

    vector shapes{ &ta, &ca, &ra, &tb, &cb, &rb }; 

     

    for (const auto& shape : shapes) { 

        cout