Write a program that defines a macro called AREA to calculat

Write a program that defines a macro called AREA to calculate the area of a circle ( PI times r times r ). The macro should have one argument, the radius. Use a preprocessor directive to define a symbolic constant PI to use in the macro. Assign a value to the radius in the main body of the program and calculate the area using the AREA macro, then output the area to the screen (you can reference the AREA macro in the cout statement if you wish). The screen output should resemble: The area of a circle with radius 3.75 is: 44.18. C++ format and preferably in codeblocks format, or notepad

Solution

#include <iostream>
#include <iomanip> //contains manipulator functions
using namespace std;

#define PI 3.1412 // constant PI defined
#define AREA(radius) PI*radius*radius // Macro AREA with parameter radius

int main(void)
{
   double radius;
   cout<<\"Enter the radius of the circle \"; //iput radius of circle
   cin>>radius;
   cout<<fixed<<setprecision(2); //manipulators
   cout<<\"\ The area of a circle with radius \"<<radius <<\" is: \"<<AREA(radius) <<\".\";//call to macro function
   return 0;
}

output: