#include <stdio.h>
int main () {
float r,s,l;
printf("输入半径：\n");
scanf("%f",&r);
s=3.14*r*r;
l=3.14*r*2;
printf("周长为:%0.2f\n",s);
printf("面积为:%0.2f\n",l);
return 0;
}