题解 | #牛牛的圆#
牛牛的圆
https://www.nowcoder.com/practice/75a202e826d048a39824ec694b5ce7e3
#include <stdio.h>
#include <math.h>
#define pi 3.14
int main()
{
double r = 0;
double result = 0;
scanf("%lf", &r);
result = pi * pow(r, 2);
printf("%.2lf", result);
return 0;
}
宏定义~~