C++ Program area of a circle with radius Example Code

#include<stdio.h>
#include<conio.h>
void main()
{
float area=0.0,radius=0.0,pi=3.14;
clrscr();
printf("enter the value of radius");
scanf("%f",&radius);
area=pi*radius*radius;
printf("area of a circle =%f",area);
   getch();
}