include <iostream> using namespace stdi float CircleArea(float r / main(): manage circle computation int maino i cout < Enter radius: i float MyRadiusi cin > MyRadius i float Area CircleArea(My Radius)i cout < circle has area l << Area return o / CircleArea(): compute area of radius r circle float CircleArea(float r)( const float pi =3.1415 return Pi*x★; 2005-4-28 自定义函数信程学院计算机技术中心2005-4-28 北京邮电大学电信工程学院计算机技术中心 -7- #include <iostream> using namespace std; float CircleArea(float r); // main(): manage circle computation int main() { cout << "Enter radius: "; float MyRadius; cin >> MyRadius; float Area = CircleArea(MyRadius); cout << "Circle has area " << Area; return 0; } // CircleArea(): compute area of radius r circle float CircleArea(float r) { const float Pi = 3.1415; return Pi * r * r; } 自定义函数