OJ Shape

问题：

Problem K: Shape系列-4

Time Limit: 1 Sec Memory Limit:
128 MB

Submit: 240 Solved: 205

[Submit][Status][Web
Board]

Description

小聪送给小亮和小华的形状他们都很喜欢,小亮和小华非要比一下他们两个的形状，来看看小聪更爱谁

，请完成RsubC类。RsubC类中包括Rectangle类和Circle类的数据成员，新增布尔类型的数据成员sign（sign等于0时，新面积等于Rectangle+Circle，sign等于1时，新面积等于Rectangle-Circle），新定义了求面积的成员函数area()。但是小聪没有为RsubC类写构造函数和成员函数，请帮助小聪完成RsubC类。

小强写的文件头和Shape类

#include<iostream>

#define PI 3.14

using namespace std;

class Shape

{

public:

Shape();

Shape(int c);

int getcolor();

double area();

protected:

int color;

};

Shape::Shape()

{

color=0;

}

Shape::Shape(int c)

{

color=c;

}

int Shape::getcolor()

{

return color;

}

double Shape::area()

{

return 10000;

}

小聪写的Rectangle类

class Rectangle:public Shape

{

public:

Rectangle(int c,double w,double h);

double getwidth();

double getheight();

double area();

double price();

protected:

double height;

double width;

};

Rectangle::Rectangle(int c,double w,double h):Shape(c)

{

width=w;

height=h;

}

double Rectangle::getwidth()

{

return width;

}

double Rectangle::getheight()

{

return height;

}

double Rectangle::area()

{

return height*width;

}

double Rectangle::price()

{

return height*width*color;

}

小聪写的Circle类

class Circle:public Shape

{

public:

Circle(int c,double r);

double getradius();

double area();

double price();

protected:

double radius;

};

Circle::Circle(int c,double r):Shape(c)

{

radius=r;

}

double Circle::getradius()

{

return radius;

}

double Circle::area()

{

return PI*radius*radius;

}

double Circle::price()

{

return PI*radius*radius*color;

}

小聪的测试函数：

int main()

{

RsubC rc=RsubC(1,2,3,1,1);

cout<<"RsubC area:"<<rc.area()<<endl;

return 0;

}

提示：不用提交全部程序，只提交补充部分。

Input

无

Output

输出小聪测试的RsubC的面积。

Sample Output

RsubC area:2.86

代码：

#include<iostream>
#define PI 3.14
using namespace std;
class Shape
{
public:
Shape();
Shape(int c);
int getcolor();
double area();
protected:
int color;
};
Shape::Shape()
{
color=0;
}
Shape::Shape(int c)
{
color=c;
}
int Shape::getcolor()
{
return color;
}
double Shape::area()
{
return 10000;
}
class Rectangle:public Shape
{
public:
Rectangle(int c,double w,double h);
double getwidth();
double getheight();
double area();
double price();
protected:
double height;
double width;
};
Rectangle::Rectangle(int c,double w,double h):Shape(c)
{
width=w;
height=h;
}
double Rectangle::getwidth()
{
return width;
}
double Rectangle::getheight()
{
return height;
}
double Rectangle::area()
{
return height*width;
}
double Rectangle::price()
{
return height*width*color;
}
class Circle:public Shape
{
public:
Circle(int c,double r);
double getradius();
double area();
double price();
protected:
double radius;
};
Circle::Circle(int c,double r):Shape(c)
{
radius=r;
}
double Circle::getradius()
{
return radius;
}
double Circle::area()
{
return PI*radius*radius;
}
double Circle::price()
{
return PI*radius*radius*color;
}
class RsubC:public Rectangle,public Circle
{
public:
RsubC(int c,double w,double h,double r,int s):Rectangle(c,w,h),Circle(c,r),sign(s){}
bool  t()
{
if(sign==1)
return true;
else
return false;
}
double area()
{
if (t())
return Rectangle::area()-Circle::area();
else
return Rectangle::area()+Circle::area();
}
private:
int sign;
};
int main()
{
RsubC rc=RsubC(1,2,3,1,1);
cout<<"RsubC area:"<<rc.area()<<endl;
return 0;
}

运行结果：



学习心得：对bool型函数的使用还不熟练，希望这次以后能够记住怎么使用。

程序修改：在新增布尔类型的数据成员sign这个位置，可以写出如下代码：

class RsubC:public Rectangle,public Circle

{

public:

.......

double area()

{

if(sign);

return Rectangle::area()-Circle::area();

else

return Rectangle::area()+Circle::area();

private:

bool sign;

}；