C++ Program to calculate area of circle
Simple C++ program to calculate area of circle: Area of circle is pi*r*r. We have used this to calculate area of circle.
#include<iostream> using namespace std; int main() { float r; float pi=3.14,area; cout<<"Enter radius of circle "; cin>>r; area=pi*(r*r); cout<<"Area of circle= "<<area<<endl; return 0; }Another C++ program to calculate area of circle using function
#include<iostream> using namespace std; float AreaOfCircle(float r) { float pi=3.14,area; area=pi*r*r; return area; } int main() { float r,area; cout<<"Enter radius of circle: "; cin>>r; area=AreaOfCircle(r); cout<<"Area of circle = "<<area; return 0; }
Another C++ Program by defining pi
In the given below program we have used #define macros to define pi as 3.14.
#include<iostream> using namespace std; #define pi 3.14 int main() { float r,area; cout<<"Enter radius of circle: "; cin>>r; area=pi*r*r; cout<<"Area of circle = "<<area; return 0; }