#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#define DEBUG
#define PI 3.1415
#define CIRCLE_AREA(r) (PI*r*r)
int main(void)
{
double radius, area;
#ifdef DEBUG
printf("“µð¹ö±ë ¸ðµåÀÔ´Ï´Ù.\n");
#endif
printf("¿øÀÇ ¹ÝÁö¸§: ");
scanf("%lf", &radius);
area = CIRCLE_AREA(radius);
printf("¿øÀÇ ¸éÀû=%.2f", area);
return 0;
}