#include <stdio.h>
#define PI 3.14
int main ()
{float r;
float c;
double area;
printf("你的半径是什么");
scanf("%f",&r);
area=PIrr;
c=PIr2;
printf("面积为%lf\n周长为%f\n",area,c);
return 0 ;
}
#include <stdio.h>
#define PI 3.14
int main ()
{float r;
float c;
double area;
printf("你的半径是什么");
scanf("%f",&r);
area=PIrr;
c=PIr2;
printf("面积为%lf\n周长为%f\n",area,c);
return 0 ;
}
#include <stdio.h>
#define PI 3.14
int main ()
{float r;
float c;
double area;
printf("你的半径是什么");
scanf("%f",&r);
area=PI*r*r;
c=PI*r*2;
printf("面积为%lf\n周长为%f\n",area,c);
return 0 ;
}