Calculate Circumference of Circle

program:

#include<stdio.h>
int main() {
   int rad;
   float Pi = 3.14, area, circum;
   printf("\nEnter radius of circle: ");
   scanf("%d", &rad);
   circum = 2 * Pi * rad;
   printf("\nCircumference is: %f ", circum);
   return (0);
}

output:

Enter radius of circle: 2

Circumference is: 12.560000