C Program to find area and circumference of circle

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

 Output :

Enter radius of a circle : 1
Area of circle : 3.14
Circumference  : 6.28

In this program we have to calculate the area and circumference of the circle. We have following 2 formulas for finding circumference and area of circle.