c++如何补充代码，求面积、周长用继承

Question

//shape.h

#ifndef SHAPE__H
#define SHAPE__H

#include
#include
static const float PI=3.14159;

class Shape{
public:

Shape():name_("Shape"),width_(0),height_(0),originx_(0),originy_(0){};

~Shape(){
    std::cout<<"~Shape() called\n";
}

public:

private:

};

class Circle: public Shape{
public:
Circle(float r): Shape(2*r,2*r,0,0,"Circle"), radius(r){
std::cout<<" Circle() called\n";
}
~Circle(){
std::cout<<" ~Circle() called\n";
}
float getarea(){
return PI*radius*radius;
}
float getperimeter(){
return 2*PI*radius;
}
private:

};

class Rectangle : public Shape{
public:

~Rectangle(){
    std::cout<<" ~Rectangle() called\n";
}

};

class Square: public Rectangle{
public:
Square(float w): Rectangle(w,w,"Square") {
std::cout<<" Square() called\n";
}
~Square(){
std::cout<<" ~Square() called\n";
}
};

#endif

//shape.cpp

#include "shape.h"
#include
#include
#include

using namespace std;

void test_1(){
cout<<"test_1 begin\n";

Shape* papers[5];
Circle michael(15);
Rectangle andrew(34.0,2.0);
Circle ann(12.5);
Square tim(9.99);
Rectangle jonathan(12.95,11.25);

papers[0] = &michael;
papers[1] = &andrew;
papers[2] = &ann;
papers[3] = &tim;
papers[4] = &jonathan;


for(int i=0;i<5;i++) {
    cout << "Shape " << setw(10) << papers[i]->getname()<<" area:" << setw(10) << papers[i]->getarea() << " perimeter:"<< setw(10)<< papers[i]->getperimeter()<< endl;
}
cout<<"test_1 end\n";

}
/* test_1 output
test_1 begin
Shape() called
Circle() called
Shape() called
Rectangle() called
Shape() called
Circle() called
Shape() called
Rectangle() called
Square() called
Shape() called
Rectangle() called
Shape Circle area: 706.858 perimeter: 94.2477
Shape Rectangle area: 68 perimeter: 72
Shape Circle area: 490.873 perimeter: 78.5397
Shape Square area: 99.8001 perimeter: 39.96
Shape Rectangle area: 145.688 perimeter: 48.4
test_1 end
~Rectangle() called
~Shape() called
~Square() called
~Rectangle() called
~Shape() called
~Circle() called
~Shape() called
~Rectangle() called
~Shape() called
~Circle() called
~Shape() called
*/

void test_2(){
cout<<"test_2 begin\n";

Shape* papers[5];
papers[0] = new Circle(15.0f);
papers[1] = new Rectangle(34.0f,2.0f);
papers[2] = new Circle(12.5f);
papers[3] = new Square(9.99f);
papers[4] = new Rectangle(12.95f,11.25f);

for(int i=0;i<5;i++) {
    cout << "Shape " << setw(10) << papers[i]->getname()<<" area:" << setw(10) << papers[i]->getarea() << " perimeter:"<< setw(10)<< papers[i]->getperimeter()<< endl;
}

for(int i=0;i<5;i++)
    delete papers[i];

cout<<"test_2 end\n";

}
/* test_2: output
test_2 begin
Shape() called
Circle() called
Shape() called
Rectangle() called
Shape() called
Circle() called
Shape() called
Rectangle() called
Square() called
Shape() called
Rectangle() called
Shape Circle area: 706.858 perimeter: 94.2477
Shape Rectangle area: 68 perimeter: 72
Shape Circle area: 490.873 perimeter: 78.5397
Shape Square area: 99.8001 perimeter: 39.96
Shape Rectangle area: 145.688 perimeter: 48.4
~Shape() called
~Shape() called
~Shape() called
~Shape() called
~Shape() called
test_2 end
*/

int main(){
test_1();
test_2();
return 0;
}

Answer 1

 class Shape
{
public:
    Shape():name_("Shape"),width_(0),height_(0),originx_(0),originy_(0)
    {

    };
    Shape(int width,int height,int originx,int originy,string name)
    {
        width_ = width;
        height_ = height;
        originx_ = originx;
        originy_ = originy;
        name_ = name;
    };
    ~Shape()
    {
        std::cout<<"~Shape() called\n";
    }
public: 
    string name_;
    int width_;
    int height_;
    int originx_;
    int originy_;
private:
};

class Circle: public Shape
{
public:
    Circle(float r): Shape(2*r,2*r,0,0,"Circle"), radius(r)
    {
        std::cout<<" Circle() called\n";
    }
    ~Circle()
    {
        std::cout<<" ~Circle() called\n";
    }
    float getarea()
    {
        return PI*radius*radius;
    }
    float getperimeter()
    {
        return 2*PI*radius;
    }
public:
    float radius;
};