Area of circle while radius is given through the keyboard

 #include<stdio.h>

#include<conio.h>

void main()

{

           int r;

           float pi=3.14,area;

    printf("enter tha radius of circle :");

    scanf("%d",&r);

           area = 3.14*r*r;

    printf("\n area of circle = %f",area);

getch ();

}

Output : 

enter tha radius of circle :6

 area of circle = 113.040001

[Process completed (code 10) - press Enter]