提交时间:2023-01-22 17:49:22

运行 ID: 6343

#include<iostream> #include<iomanip> using namespace std; int main() { float r; cin>>r; float d=r*2; cout<<fixed<<setprecision(4)<<d<<" "; float c=3.14159*d; cout<<fixed<<setprecision(4)<<c<<" "; float s=3.14159*r*r; cout<<fixed<<setprecision(4)<<s<<" "; return 0; }