提交时间:2023-02-04 16:40:22

运行 ID: 7547

#include<iostream> #include<iomanip> using namespace std; int main () { int r; cin>>r; double p=3.14159; double z=1.0*2*p*r; double m=1.0*p*r*r; cout<<fixed<<setprecision(4)<<1.0*2*r<<" "; cout<<fixed<<setprecision(4)<<z<<" "; cout<<fixed<<setprecision(4)<<m; }