C++ Learning Log 26--Array of Objects

---

First, the construction of the object array

#include<iostream>
#include"circle.h"

int main()
{
    
    
    Circle ca1[]{
    
     Circle{
    
    1.0},Circle{
    
    2.0},Circle{
    
    3.0} };
    Circle ca2[]{
    
     10.0,11.0,12.0 };

    ca1[2].setRadius(4.0);
    ca2[1].setRadius(100.0);

    auto area1{
    
     0.0 };
    auto area2{
    
     0.0 };

    for (int i = 0; i < static_cast<int>(sizeof(ca1) / sizeof(ca1[0])); i++)
    {
    
    
        std::cout << ca1[i].getArea() << std::endl;
        area1 += ca1[i].getArea();
    }

    for (auto x : ca2)
    {
    
    
        std::cout << x.getArea() << std::endl;
        area2 += x.getArea();
    }

    std::cout << "ca1's area : "<<area1 << std::endl;

    std::cout << "ca2's area : " << area2 << std::endl;
    return 0;


}

2. Related.c

#include"circle.h"
Circle::Circle()
{
    
    
	radius = 1.0;
}
Circle::Circle(double radius_)
{
    
    
	radius = radius_;
}
double Circle::getArea()
{
    
    
	return (3.14 * radius * radius);

}
double Circle::getRadius() const
{
    
    
	return radius;
}

void Circle::setRadius(double radius)
{
    
    
	this->radius = radius;
}

3. Related.h

#pragma once

class Circle
{
    
    
private:
	double radius;
public:
	Circle();
	Circle(double radius_);
	double getArea();
public:
	double getRadius() const;
	void setRadius(double radius);

};