题解 | #牛牛的圆#
牛牛的圆
https://www.nowcoder.com/practice/75a202e826d048a39824ec694b5ce7e3
知识点：运算
#include <iostream>
#include <cmath>
#include <iomanip>
using namespace std;
int main() {
int r = 0;
float pi = 3.14;
float area = 0.0;
cin >> r;
area = pi * pow(r, 2);
cout << fixed << setprecision(2);
cout << area;
return 0;
}
#算法#