//by Maksim Ivanenko
	//class example

#include <iostream.h>
#include <math.h>

//function prototype
void display(float area,float radius);

//main program
void main()

{
		//declare variables & constants
		float radius,area;
		const float pi=(float)3.14159;

		//input
		cout<< "Enter radius   ";
		cin>> radius;

		//process
		area=pi*(float)pow(radius,2);

		//output
		display(area,radius);	//to call on function
		
}

void display(float area,float radius)
//link in paranpherses for variable arguments
{
	
	cout<<"Area is " <<area<<endl;
	cout<<"Area of this radius "<<radius<<" calculated."<<endl;
}

/*
Enter radius   12.32
Area is 476.838
Area of this radius 12.32 calculated.
*/