c++问题,c++高手请进!!!答得满意给加分!

来源:百度知道 编辑:UC知道 时间:2024/05/22 23:56:18
题:声明一个circle类,有数据成员radius(半径),成员函数getarea(),计算圆的面积,构造一个circle的对象进行测试。
#include"iostream"
using namespace std;
const float pi = 3.14;
class circle
{
public:
getarea(float r);
private:
float radius;
}
circle::getarea(float r)
{ radius = r;
float newarea;
newarea = 0.5 * pi * radius * radius;
return newarea;
}
int main()
{ float n; float wanarea;
circle mycircle;
cin>>n;
wanarea = mycircle.getarea(n);
cout<<wanarea<<endl;
return(0);
}
请高手帮我看看这个程序错在哪里了,并指出为什么错了,需要怎么改?
谢谢!!!

//欢迎在线讨论
#include <iostream>
using namespace std;

const double pi = 3.14;
class circle
{
public:
getarea(float r);
private:
float radius;
};
circle::getarea(float r)
{
radius = r;
float newarea;
newarea = 0.5 * pi * radius * radius;
return newarea;
}
int main()
{
float n;
float wanarea;
circle mycircle;
cin>>n;
wanarea = mycircle.getarea(n);
cout<<wanarea<<endl;
return(0);
}

关注此问题

#include<iostream>
using namespace std;
const float pi = 3.14;
class circle
{
public:
float getarea(float r);
private:
float radius;
}
float circle::getarea(float r)
{ radius = r;
float newarea;
newarea = 0.5 * pi * radius * radius;
return newarea;
}
int main()
{
float n;
floa