C Programming Code Examples
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C Program to calculate Area and Circumference of Circle
/* C Program to calculate Area and Circumference of Circle
To calculate area and circumference we must know the radius of circle. The program will prompt user to enter the radius and based on the input it would calculate the values. To make it simpler we have taken standard PI value as 3.14 (constant) in the program. Other details are mentioned as comments in the below example program.
Formula:
Area = 3.14 * radius * radius
Circumference = 2 * 3.14 * radius */
#include <stdio.h>
int main()
{
int circle_radius;
float PI_VALUE=3.14, circle_area, circle_circumf;
//Ask user to enter the radius of circle
printf("\nEnter radius of circle: ");
//Storing the user input into variable circle_radius
scanf("%d",&circle_radius);
//Calculate and display Area
circle_area = PI_VALUE * circle_radius * circle_radius;
printf("\nArea of circle is: %f",circle_area);
//Caluclate and display Circumference
circle_circumf = 2 * PI_VALUE * circle_radius;
printf("\nCircumference of circle is: %f",circle_circumf);
return(0);
}
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