題目二
#include <stdio.h>
#define pi 3.14
double calculateArea (int radius);
int main()
{
int cRadius = 0;
double area = 0.0;
printf("輸入圓的半徑：\n");
scanf("%d",&cRadius);
area = calculateArea(cRadius);
printf("圓面積是：%f \n",area);
return 0;
}
double calculateArea (int radius)
{
double result = pi* radius*radius;
return result;
}
