Program to calculate the area of a circle

#include <stdio.h>
 
int main() {
   float radius, area_circle;
 
   // take radius as input
   printf("Enter the radius of circle : ");
   scanf("%f", &radius);
 
   area_circle = 3.14 * radius * radius;
   printf("Area of circle : %f", area_circle);
 
   return 0;
}