WRITE A FUNCTION TO FIND AREA OF A SPHERE

#include<conio.h>
#include<stdio.h>
#define PI 3.14
void main()
{
void area(int);
int r;
clrscr();
printf("enter the radius\n");
scanf("%d",&r);
area(r);
getch();
}

void area(int r)
{
float a;
a=4*PI*r*r;
printf("the area of sphere is %f",a);
}