请编写程序求圆形的面积并把3.1415926的值定义为符号常量pi

也没说用啥语言,用C语言写了#include #define PI 3。1415926int main(void){float r = 0。0;float s = 0。0;printf("Please input the radius of circle:\n");scanf("%f",&r);s = PI * r * r;printf("The area of the circle is %f\n",s);return 0;}