All Notes on BCA

#include<stdio.h>
#include<conio.h>
void main()
{
float r,area,pi=3.14;
clrscr();
 printf("Enter radius : ");
 scanf("%f",&r);
  area=pi*r*r;
 printf("Area of Circle : %f",area);
 getch();
}

INPUT
Enter radius : 5
OUTPUT
Area of Circle : 78.5