提交时间:2023-02-02 12:45:06
运行 ID: 7238
#include <iostream> #include <iomanip> using namespace std; int main(){ double r; const double PI = 3.14159; cin>>r; cout<<fixed<<setprecision(4)<<2 * r<<" "<<2 * PI * r<<" "<<PI * r * r<<endl; return 0; }