pgrm_004.cpp (801B)
1 /* Write a program to calculate area and circumference of a circle. */ 2 3 #include<iostream> 4 #include<cmath> 5 using namespace std; 6 7 class circle { 8 private: 9 double r, radius; 10 11 public: 12 circle(double r) { 13 setRadius(r); 14 } 15 ~circle() {}; 16 17 void setRadius(double r) { 18 if(r >= 0) radius = r; 19 else radius = 0; 20 } 21 22 double getRadius() { 23 return radius; 24 } 25 26 double area() { 27 return M_PI * radius * radius; 28 } 29 30 double cir() { 31 return 2 * M_PI * radius; 32 } 33 }; 34 35 int main() { 36 circle c(5); 37 cout << "Radius: " << c.getRadius() << endl; 38 cout << "Area: " << c.area() << endl; 39 cout << "Circumference: " << c.cir() << endl; 40 return 0; 41 }