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前言
🎬本文章是 【C++笔记】 专栏的文章，主要是C++黑马的笔记、自己的实验与课设
🔗C++笔记 传送门
一、要求
编写一个程序计算三角形、正方形、圆的面积,要求抽象出一个基类 CBase ,在抽象类中设计两个纯虚函数,分别用来求面积和周长
二、分析
由要求分析可知，在Cbase类中声明纯虚函数，之后在Triangle类、Cube类、Circle类分别对两个函数重写，在main函数中通过指针调用
三、代码
💻提示：所有实验源码已在github整理
#include<iostream>
using namespace std;
#define PI 3.1415926
class CBase
{
public:
virtual void area() = 0;
virtual void circum() = 0;
};
class Triangle :public CBase
{
public:
Triangle(double d, double h, double a, double b, double c)
{
this->d = d;
this->h = h;
this->a = a;
this->b = b;
this->c = c;
}
void area()
{
cout << "三角形的面积为" << d * h/2 << endl;
}
void circum()
{
cout << "三角形的周长为" << a + b + c << endl;
}
private:
double d;
double h;
double a;//定义三条边a,b,c
double b;
double c;
};
class Cube :public CBase
{
public:
Cube(double c)
{
this->c = c;
}
void area()
{
cout << "长方形的面积为" << c * c << endl;
}
void circum()
{
cout << "长方形的周长为" << 4 * c << endl;
}
private:
double c;
};
class Circle :public CBase
{
public:
Circle(double r)
{
this->r = r;
}
void area()
{
cout << "圆的面积为" << PI * r*r << endl;
}
void circum()
{
cout << "圆的周长为" << 2 * PI*r << endl;
}
private:
double r;
};
int main()
{
CBase * t = new Triangle(3, 4, 3, 4, 5);
t->area();
t->circum();
delete t;
CBase * c = new Cube(1);
c->area();
c->circum();
delete c;
CBase * cir = new Circle(1);
cir->area();
cir->circum();
delete cir;
system("pause");
return 0;
}
