题解 | 牛牛的圆
牛牛的圆
https://www.nowcoder.com/practice/75a202e826d048a39824ec694b5ce7e3
#include <stdio.h>
#define pi 3.14
int main() {
int r = 0;
scanf("%d",&r);
float area = 0;
area = pi * r * r;
printf("%.2f",area);
return 0;
}
