c++定义一个圆类计算面积和半径，要求如下，谢谢~

复制构造函数有点忘了，下面是基本的功能 ，你完善一下吧。
#include

#define pi 3.1415926 //∏，当然也可以写成3.14；或是不写，在计算时直接用

class Circle{
float r; //半径
float c; //周长
float s; //面积
public:
Circle(float tr=0)
{
r=tr;
c=2*pi*r;
s=pi*r*r;
}

~Circle() //这里千万不能忘了(析构函数)
{
}
void show()
{
cout<<"圆的半径:r="< cout<<"圆的周长:c="< cout<<"圆的面积:s="< cout< }
};

void main()
{
float ra;
cout<<"请输入圆的半径r:"< cin>>ra;
Circle cir(ra);
cir.show();
}

#include
using namespace std;

#define pi 3.14

class circle
{
public:
circle(double r=0.0){}
circle(circle &c){}
double circumference();
double area();
void cinradius();
double coutradius(){return radius;}

private:
double radius;
};

double circle::circumference()
{
return 2*pi*radius;
}

double circle::area()
{
return pi*radius*radius;
}

void circle::cinradius()
{
cout< <<"请输入半径：";
cin>>radius;
}

int main()
{
circle CIR;

CIR.cinradius();

cout<<"半径："
<
cout< <<"圆的周长为"
< < <<"圆的面积为"
<
return 0;
}

#include
using
namespace
std;
#define
pi
3.14
class
circle
{
public:
circle(double
r=0.0){}
circle(circle
&c){}
double
circumference();
double
area();
void
cinradius();
double
coutradius(){return
radius;}
private:
double
radius;
};
double
circle::circumference()
{
return
2*pi*radius;
}
double
circle::area()
{
return
pi*radius*radius;
}
void
circle::cinradius()
{
cout<<<"请输入半径：";
cin>>radius;
}
int
main()
{
circle
CIR;
CIR.cinradius();
cout<<"半径："
<cout<<<"圆的周长为"
<<<<"圆的面积为"
<return
0;
}